816015901 has 4 divisors (see below), whose sum is σ = 816074812. Its totient is φ = 815956992.

The previous prime is 816015881. The next prime is 816015923. The reversal of 816015901 is 109510618.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 92352100 + 723663801 = 9610^2 + 26901^2 .

It is a cyclic number.

It is not a de Polignac number, because 816015901 - 2¹¹ = 816013853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816015301) 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, 3955 + ... + 40591.

It is an arithmetic number, because the mean of its divisors is an integer number (204018703).

Almost surely, 2^816015901 is an apocalyptic number.

It is an amenable number.

816015901 is a deficient number, since it is larger than the sum of its proper divisors (58911).

816015901 is a wasteful number, since it uses less digits than its factorization.

816015901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58910.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 816015901 is about 28565.9920359857. The cubic root of 816015901 is about 934.4718154600.

The spelling of 816015901 in words is "eight hundred sixteen million, fifteen thousand, nine hundred one".