401656279081 has 4 divisors (see below), whose sum is σ = 403737399892. Its totient is φ = 399575158272.

The previous prime is 401656278977. The next prime is 401656279153. The reversal of 401656279081 is 180972656104.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 41650279056 + 360006000025 = 204084^2 + 600005^2 .

It is a cyclic number.

It is not a de Polignac number, because 401656279081 - 2²⁵ = 401622724649 is a prime.

It is a super-2 number, since 2×401656279081² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401656276081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1040560116 + ... + 1040560501.

It is an arithmetic number, because the mean of its divisors is an integer number (100934349973).

Almost surely, 2^401656279081 is an apocalyptic number.

It is an amenable number.

401656279081 is a deficient number, since it is larger than the sum of its proper divisors (2081120811).

401656279081 is a wasteful number, since it uses less digits than its factorization.

401656279081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2081120810.

The product of its (nonzero) digits is 725760, while the sum is 49.

The spelling of 401656279081 in words is "four hundred one billion, six hundred fifty-six million, two hundred seventy-nine thousand, eighty-one".