815716401 has 4 divisors (see below), whose sum is σ = 1087621872. Its totient is φ = 543810932.

The previous prime is 815716399. The next prime is 815716409. The reversal of 815716401 is 104617518.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 815716401 - 2¹ = 815716399 is a prime.

It is not an unprimeable number, because it can be changed into a prime (815716409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135952731 + ... + 135952736.

It is an arithmetic number, because the mean of its divisors is an integer number (271905468).

Almost surely, 2^815716401 is an apocalyptic number.

It is an amenable number.

815716401 is a deficient number, since it is larger than the sum of its proper divisors (271905471).

815716401 is a wasteful number, since it uses less digits than its factorization.

815716401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271905470.

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 815716401 is about 28560.7493073974. The cubic root of 815716401 is about 934.3574759576.

The spelling of 815716401 in words is "eight hundred fifteen million, seven hundred sixteen thousand, four hundred one".