71220006 has 128 divisors (see below), whose sum is σ = 194503680. Its totient is φ = 19008000.

The previous prime is 71219977. The next prime is 71220007. The reversal of 71220006 is 60002217.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71220007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 177406 + ... + 177806.

It is an arithmetic number, because the mean of its divisors is an integer number (1519560).

Almost surely, 2^71220006 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71220006, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97251840).

71220006 is an abundant number, since it is smaller than the sum of its proper divisors (123283674).

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

71220006 is a wasteful number, since it uses less digits than its factorization.

71220006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 71220006 is about 8439.1946298210. The cubic root of 71220006 is about 414.5090356919.

The spelling of 71220006 in words is "seventy-one million, two hundred twenty thousand, six".