71990754521 has 4 divisors (see below), whose sum is σ = 82275148032. Its totient is φ = 61706361012.

The previous prime is 71990754509. The next prime is 71990754533. The reversal of 71990754521 is 12545709917.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (71990754509) and next prime (71990754533).

It is a cyclic number.

It is not a de Polignac number, because 71990754521 - 2¹⁴ = 71990738137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71990754521.

It is not an unprimeable number, because it can be changed into a prime (71990754551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5142196745 + ... + 5142196758.

It is an arithmetic number, because the mean of its divisors is an integer number (20568787008).

Almost surely, 2^71990754521 is an apocalyptic number.

It is an amenable number.

71990754521 is a deficient number, since it is larger than the sum of its proper divisors (10284393511).

71990754521 is a wasteful number, since it uses less digits than its factorization.

71990754521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10284393510.

The product of its (nonzero) digits is 793800, while the sum is 50.

The spelling of 71990754521 in words is "seventy-one billion, nine hundred ninety million, seven hundred fifty-four thousand, five hundred twenty-one".