78171400977 has 16 divisors (see below), whose sum is σ = 104880437760. Its totient is φ = 51789140352.

The previous prime is 78171400969. The next prime is 78171400981. The reversal of 78171400977 is 77900417187.

It is not a de Polignac number, because 78171400977 - 2³ = 78171400969 is a prime.

It is a super-2 number, since 2×78171400977² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78171400877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 277983 + ... + 483339.

It is an arithmetic number, because the mean of its divisors is an integer number (6555027360).

Almost surely, 2^78171400977 is an apocalyptic number.

It is an amenable number.

78171400977 is a deficient number, since it is larger than the sum of its proper divisors (26709036783).

78171400977 is a wasteful number, since it uses less digits than its factorization.

78171400977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206152.

The product of its (nonzero) digits is 691488, while the sum is 51.

The spelling of 78171400977 in words is "seventy-eight billion, one hundred seventy-one million, four hundred thousand, nine hundred seventy-seven".