72121252577 has 4 divisors (see below), whose sum is σ = 78677730096. Its totient is φ = 65564775060.

The previous prime is 72121252573. The next prime is 72121252583. The reversal of 72121252577 is 77525212127.

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 a cyclic number.

It is not a de Polignac number, because 72121252577 - 2² = 72121252573 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72121252573) 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, 3278238743 + ... + 3278238764.

It is an arithmetic number, because the mean of its divisors is an integer number (19669432524).

Almost surely, 2^72121252577 is an apocalyptic number.

It is an amenable number.

72121252577 is a deficient number, since it is larger than the sum of its proper divisors (6556477519).

72121252577 is a wasteful number, since it uses less digits than its factorization.

72121252577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6556477518.

The product of its digits is 137200, while the sum is 41.

The spelling of 72121252577 in words is "seventy-two billion, one hundred twenty-one million, two hundred fifty-two thousand, five hundred seventy-seven".