71251020 has 108 divisors (see below), whose sum is σ = 225091776. Its totient is φ = 18224640.

The previous prime is 71250973. The next prime is 71251021. The reversal of 71251020 is 2015217.

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

It is a junction number, because it is equal to n+sod(n) for n = 71250984 and 71251002.

It is not an unprimeable number, because it can be changed into a prime (71251021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 630484 + ... + 630596.

Almost surely, 2^71251020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71251020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112545888).

71251020 is an abundant number, since it is smaller than the sum of its proper divisors (153840756).

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

71251020 is a wasteful number, since it uses less digits than its factorization.

71251020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 71251020 is about 8441.0319274364. The cubic root of 71251020 is about 414.5691953687.

Adding to 71251020 its reverse (2015217), we get a palindrome (73266237).

The spelling of 71251020 in words is "seventy-one million, two hundred fifty-one thousand, twenty".