400778270651 has 4 divisors (see below), whose sum is σ = 437212658904. Its totient is φ = 364343882400.

The previous prime is 400778270621. The next prime is 400778270687. The reversal of 400778270651 is 156072877004.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 400778270651 - 2²² = 400774076347 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 400778270596 and 400778270605.

It is not an unprimeable number, because it can be changed into a prime (400778270621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18217194110 + ... + 18217194131.

It is an arithmetic number, because the mean of its divisors is an integer number (109303164726).

Almost surely, 2^400778270651 is an apocalyptic number.

400778270651 is a deficient number, since it is larger than the sum of its proper divisors (36434388253).

400778270651 is a wasteful number, since it uses less digits than its factorization.

400778270651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36434388252.

The product of its (nonzero) digits is 658560, while the sum is 47.

The spelling of 400778270651 in words is "four hundred billion, seven hundred seventy-eight million, two hundred seventy thousand, six hundred fifty-one".