399581155 has 16 divisors (see below), whose sum is σ = 491651424. Its totient is φ = 311592960.

The previous prime is 399581137. The next prime is 399581177. The reversal of 399581155 is 551185993.

It is not a de Polignac number, because 399581155 - 2¹⁷ = 399450083 is a prime.

It is a super-2 number, since 2×399581155² = 319330198862268050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122445 + ... + 125665.

It is an arithmetic number, because the mean of its divisors is an integer number (30728214).

Almost surely, 2^399581155 is an apocalyptic number.

399581155 is a deficient number, since it is larger than the sum of its proper divisors (92070269).

399581155 is a wasteful number, since it uses less digits than its factorization.

399581155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3846.

The product of its digits is 243000, while the sum is 46.

The square root of 399581155 is about 19989.5261324525. The cubic root of 399581155 is about 736.5490368840.

The spelling of 399581155 in words is "three hundred ninety-nine million, five hundred eighty-one thousand, one hundred fifty-five".