406251391815 has 64 divisors (see below), whose sum is σ = 765303707520. Its totient is φ = 203763548160.

The previous prime is 406251391813. The next prime is 406251391823. The reversal of 406251391815 is 518193152604.

It is a happy number.

406251391815 is a `hidden beast` number, since 4 + 0 + 6 + 251 + 391 + 8 + 1 + 5 = 666.

It is not a de Polignac number, because 406251391815 - 2¹ = 406251391813 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406251391813) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2908375 + ... + 3044855.

It is an arithmetic number, because the mean of its divisors is an integer number (11957870430).

Almost surely, 2^406251391815 is an apocalyptic number.

406251391815 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

406251391815 is a deficient number, since it is larger than the sum of its proper divisors (359052315705).

406251391815 is a wasteful number, since it uses less digits than its factorization.

406251391815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137809 (or 137803 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 45.

The spelling of 406251391815 in words is "four hundred six billion, two hundred fifty-one million, three hundred ninety-one thousand, eight hundred fifteen".