916401492581 has 4 divisors (see below), whose sum is σ = 916425711852. Its totient is φ = 916377273312.

The previous prime is 916401492553. The next prime is 916401492593. The reversal of 916401492581 is 185294104619.

It is a happy number.

916401492581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 419988244225 + 496413248356 = 648065^2 + 704566^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-916401492581 is a prime.

It is a super-2 number, since 2×916401492581² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (916401492511) 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, 12052790 + ... + 12128583.

It is an arithmetic number, because the mean of its divisors is an integer number (229106427963).

Almost surely, 2^916401492581 is an apocalyptic number.

It is an amenable number.

916401492581 is a deficient number, since it is larger than the sum of its proper divisors (24219271).

916401492581 is a wasteful number, since it uses less digits than its factorization.

916401492581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24219270.

The product of its (nonzero) digits is 622080, while the sum is 50.

The spelling of 916401492581 in words is "nine hundred sixteen billion, four hundred one million, four hundred ninety-two thousand, five hundred eighty-one".