400039998 has 16 divisors (see below), whose sum is σ = 800476176. Its totient is φ = 133280640.

The previous prime is 400039987. The next prime is 400039999. The reversal of 400039998 is 899930004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400039999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2461 + ... + 28392.

It is an arithmetic number, because the mean of its divisors is an integer number (50029761).

Almost surely, 2^400039998 is an apocalyptic number.

400039998 is an abundant number, since it is smaller than the sum of its proper divisors (400436178).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400039998 is a wasteful number, since it uses less digits than its factorization.

400039998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33019.

The product of its (nonzero) digits is 69984, while the sum is 42.

The square root of 400039998 is about 20000.9999250037. Note that the first 4 decimals coincide. The cubic root of 400039998 is about 736.8308578915.

The spelling of 400039998 in words is "four hundred million, thirty-nine thousand, nine hundred ninety-eight".