71972180 has 54 divisors (see below), whose sum is σ = 176468922. Its totient is φ = 24585120.

The previous prime is 71972167. The next prime is 71972183. The reversal of 71972180 is 8127917.

It can be written as a sum of positive squares in only one way, i.e., 57577744 + 14394436 = 7588^2 + 3794^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 71972180.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71972183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 265445 + ... + 265715.

It is an arithmetic number, because the mean of its divisors is an integer number (3267943).

Almost surely, 2^71972180 is an apocalyptic number.

71972180 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71972180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88234461).

71972180 is an abundant number, since it is smaller than the sum of its proper divisors (104496742).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71972180 is a wasteful number, since it uses less digits than its factorization.

71972180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565 (or 285 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 71972180 is about 8483.6419066342. The cubic root of 71972180 is about 415.9631762893.

The spelling of 71972180 in words is "seventy-one million, nine hundred seventy-two thousand, one hundred eighty".