778151572641 has 9 divisors (see below), whose sum is σ = 1124000538609. Its totient is φ = 518765950836.

The previous prime is 778151572619. The next prime is 778151572663. The reversal of 778151572641 is 146275151877.

It is a happy number.

The square root of 778151572641 is 882129.

It is a perfect power (a square), and thus also a powerful number.

778151572641 is a `hidden beast` number, since 7 + 7 + 8 + 1 + 5 + 1 + 572 + 64 + 1 = 666.

778151572641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (778151572619) and next prime (778151572663).

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 778151572641 - 2¹¹ = 778151570593 is a prime.

It is a super-2 number, since 2×778151572641² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (778151572441) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2499366 + ... + 2793408.

Almost surely, 2^778151572641 is an apocalyptic number.

778151572641 is the 882129-th square number.

778151572641 is the 441065-th centered octagonal number.

It is an amenable number.

778151572641 is a deficient number, since it is larger than the sum of its proper divisors (345848965968).

778151572641 is an frugal number, since it uses more digits than its factorization.

778151572641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588092 (or 294046 counting only the distinct ones).

The product of its digits is 3292800, while the sum is 54.

The spelling of 778151572641 in words is "seven hundred seventy-eight billion, one hundred fifty-one million, five hundred seventy-two thousand, six hundred forty-one".