77028951491 has 4 divisors (see below), whose sum is σ = 78334527000. Its totient is φ = 75723375984.

The previous prime is 77028951487. The next prime is 77028951499. The reversal of 77028951491 is 19415982077.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 77028951491 - 2² = 77028951487 is a prime.

It is a super-2 number, since 2×77028951491² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77028951499) 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, 652787666 + ... + 652787783.

It is an arithmetic number, because the mean of its divisors is an integer number (19583631750).

Almost surely, 2^77028951491 is an apocalyptic number.

77028951491 is a deficient number, since it is larger than the sum of its proper divisors (1305575509).

77028951491 is a wasteful number, since it uses less digits than its factorization.

77028951491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1305575508.

The product of its (nonzero) digits is 1270080, while the sum is 53.

The spelling of 77028951491 in words is "seventy-seven billion, twenty-eight million, nine hundred fifty-one thousand, four hundred ninety-one".