7921152891 has 112 divisors (see below), whose sum is σ = 12833114112. Its totient is φ = 4877884800.

The previous prime is 7921152859. The next prime is 7921152913. The reversal of 7921152891 is 1982511297.

7921152891 = 335² + 336² + ... + 2876².

It is not a de Polignac number, because 7921152891 - 2⁵ = 7921152859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7921150891) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 76904346 + ... + 76904448.

It is an arithmetic number, because the mean of its divisors is an integer number (114581376).

Almost surely, 2^7921152891 is an apocalyptic number.

7921152891 is a deficient number, since it is larger than the sum of its proper divisors (4911961221).

7921152891 is a wasteful number, since it uses less digits than its factorization.

7921152891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276 (or 261 counting only the distinct ones).

The product of its digits is 90720, while the sum is 45.

The square root of 7921152891 is about 89000.8589340575. The cubic root of 7921152891 is about 1993.4077022628.

The spelling of 7921152891 in words is "seven billion, nine hundred twenty-one million, one hundred fifty-two thousand, eight hundred ninety-one".