400642515 has 96 divisors (see below), whose sum is σ = 860461056. Its totient is φ = 167927040.

The previous prime is 400642399. The next prime is 400642537. The reversal of 400642515 is 515246004.

400642515 is a `hidden beast` number, since 4 + 0 + 0 + 642 + 5 + 15 = 666.

It is not a de Polignac number, because 400642515 - 2⁷ = 400642387 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 929350 + ... + 929780.

It is an arithmetic number, because the mean of its divisors is an integer number (8963136).

Almost surely, 2^400642515 is an apocalyptic number.

400642515 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

400642515 is an abundant number, since it is smaller than the sum of its proper divisors (459818541).

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

400642515 is a wasteful number, since it uses less digits than its factorization.

400642515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 686 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 400642515 is about 20016.0564297766. The cubic root of 400642515 is about 737.2005962686.

Adding to 400642515 its reverse (515246004), we get a palindrome (915888519).

The spelling of 400642515 in words is "four hundred million, six hundred forty-two thousand, five hundred fifteen".