7966920581 has 4 divisors (see below), whose sum is σ = 7967531712. Its totient is φ = 7966309452.

The previous prime is 7966920557. The next prime is 7966920607. The reversal of 7966920581 is 1850296697.

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 a de Polignac number, because none of the positive numbers 2^k-7966920581 is a prime.

It is a super-2 number, since 2×7966920581² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7966020581) 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, 285575 + ... + 312228.

It is an arithmetic number, because the mean of its divisors is an integer number (1991882928).

Almost surely, 2^7966920581 is an apocalyptic number.

It is an amenable number.

7966920581 is a deficient number, since it is larger than the sum of its proper divisors (611131).

7966920581 is a wasteful number, since it uses less digits than its factorization.

7966920581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611130.

The product of its (nonzero) digits is 1632960, while the sum is 53.

The square root of 7966920581 is about 89257.6079726541. The cubic root of 7966920581 is about 1997.2395735257.

The spelling of 7966920581 in words is "seven billion, nine hundred sixty-six million, nine hundred twenty thousand, five hundred eighty-one".