71520538 has 4 divisors (see below), whose sum is σ = 107280810. Its totient is φ = 35760268.

The previous prime is 71520473. The next prime is 71520539. The reversal of 71520538 is 83502517.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 66308449 + 5212089 = 8143^2 + 2283^2 .

It is not an unprimeable number, because it can be changed into a prime (71520539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17880133 + ... + 17880136.

Almost surely, 2^71520538 is an apocalyptic number.

71520538 is a deficient number, since it is larger than the sum of its proper divisors (35760272).

71520538 is a wasteful number, since it uses less digits than its factorization.

71520538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35760271.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 71520538 is about 8456.9816128451. The cubic root of 71520538 is about 415.0912616829.

The spelling of 71520538 in words is "seventy-one million, five hundred twenty thousand, five hundred thirty-eight".