71521479 has 12 divisors (see below), whose sum is σ = 103389936. Its totient is φ = 47643552.

The previous prime is 71521459. The next prime is 71521493. The reversal of 71521479 is 97412517.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-71521479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71521459) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13819 + ... + 18275.

It is an arithmetic number, because the mean of its divisors is an integer number (8615828).

Almost surely, 2^71521479 is an apocalyptic number.

71521479 is the 5349-th heptagonal number.

71521479 is a deficient number, since it is larger than the sum of its proper divisors (31868457).

71521479 is a wasteful number, since it uses less digits than its factorization.

71521479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6246 (or 6243 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 71521479 is about 8457.0372471688. The cubic root of 71521479 is about 415.0930821351.

The spelling of 71521479 in words is "seventy-one million, five hundred twenty-one thousand, four hundred seventy-nine".