778554397972 has 96 divisors (see below), whose sum is σ = 1533096320000. Its totient is φ = 343561720320.

The previous prime is 778554397949. The next prime is 778554397987. The reversal of 778554397972 is 279793455877.

It is a super-2 number, since 2×778554397972² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 778554397895 and 778554397904.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 155739529 + ... + 155744527.

Almost surely, 2^778554397972 is an apocalyptic number.

It is an amenable number.

778554397972 is a deficient number, since it is larger than the sum of its proper divisors (754541922028).

778554397972 is a wasteful number, since it uses less digits than its factorization.

778554397972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6441 (or 6439 counting only the distinct ones).

The product of its digits is 933508800, while the sum is 73.

The spelling of 778554397972 in words is "seven hundred seventy-eight billion, five hundred fifty-four million, three hundred ninety-seven thousand, nine hundred seventy-two".