78728611251 has 8 divisors (see below), whose sum is σ = 108357658624. Its totient is φ = 50792652360.

The previous prime is 78728611229. The next prime is 78728611253. The reversal of 78728611251 is 15211682787.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78728611251 - 2²¹ = 78726514099 is a prime.

It is a super-2 number, since 2×78728611251² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78728611251.

It is not an unprimeable number, because it can be changed into a prime (78728611253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 423272011 + ... + 423272196.

It is an arithmetic number, because the mean of its divisors is an integer number (13544707328).

Almost surely, 2^78728611251 is an apocalyptic number.

78728611251 is a deficient number, since it is larger than the sum of its proper divisors (29629047373).

78728611251 is a wasteful number, since it uses less digits than its factorization.

78728611251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846544241.

The product of its digits is 376320, while the sum is 48.

The spelling of 78728611251 in words is "seventy-eight billion, seven hundred twenty-eight million, six hundred eleven thousand, two hundred fifty-one".