401639165 has 8 divisors (see below), whose sum is σ = 482135640. Its totient is φ = 321198912.

The previous prime is 401639149. The next prime is 401639171. The reversal of 401639165 is 561936104.

It can be written as a sum of positive squares in 4 ways, for example, as 9084196 + 392554969 = 3014^2 + 19813^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 401639165 - 2⁴ = 401639149 is a prime.

It is a super-2 number, since 2×401639165² = 322628037723794450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3707 + ... + 28583.

It is an arithmetic number, because the mean of its divisors is an integer number (60266955).

Almost surely, 2^401639165 is an apocalyptic number.

It is an amenable number.

401639165 is a deficient number, since it is larger than the sum of its proper divisors (80496475).

401639165 is a wasteful number, since it uses less digits than its factorization.

401639165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28111.

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 401639165 is about 20040.9372285829. The cubic root of 401639165 is about 737.8113839752.

The spelling of 401639165 in words is "four hundred one million, six hundred thirty-nine thousand, one hundred sixty-five".