399998129755 has 64 divisors (see below), whose sum is σ = 587546265600. Its totient is φ = 255327759360.

The previous prime is 399998129693. The next prime is 399998129777. The reversal of 399998129755 is 557921899993.

It is not a de Polignac number, because 399998129755 - 2¹⁵ = 399998096987 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13043290 + ... + 13073920.

It is an arithmetic number, because the mean of its divisors is an integer number (9180410400).

Almost surely, 2^399998129755 is an apocalyptic number.

399998129755 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

399998129755 is a deficient number, since it is larger than the sum of its proper divisors (187548135845).

399998129755 is a wasteful number, since it uses less digits than its factorization.

399998129755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31004.

The product of its digits is 496011600, while the sum is 76.

The spelling of 399998129755 in words is "three hundred ninety-nine billion, nine hundred ninety-eight million, one hundred twenty-nine thousand, seven hundred fifty-five".