77434504578 has 30 divisors (see below), whose sum is σ = 173518585779. Its totient is φ = 25810320924.

The previous prime is 77434504571. The next prime is 77434504601. The reversal of 77434504578 is 87540543477.

It can be written as a sum of positive squares in only one way, i.e., 38717252289 + 38717252289 = 196767^2 + 196767^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=196767.

It is a super-2 number, since 2×77434504578² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (77434504571) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 3530875 + ... + 3552737.

Almost surely, 2^77434504578 is an apocalyptic number.

77434504578 is an abundant number, since it is smaller than the sum of its proper divisors (96084081201).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77434504578 is an frugal number, since it uses more digits than its factorization.

77434504578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43740 (or 21868 counting only the distinct ones).

The product of its (nonzero) digits is 13171200, while the sum is 54.

The spelling of 77434504578 in words is "seventy-seven billion, four hundred thirty-four million, five hundred four thousand, five hundred seventy-eight".