916367981 has 4 divisors (see below), whose sum is σ = 918062364. Its totient is φ = 914673600.

The previous prime is 916367971. The next prime is 916367987. The reversal of 916367981 is 189763619.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 189763619 = 61 ⋅3110879.

It can be written as a sum of positive squares in 2 ways, for example, as 570779881 + 345588100 = 23891^2 + 18590^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-916367981 is a prime.

It is a super-2 number, since 2×916367981² = 1679460553204032722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (916367987) 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, 846380 + ... + 847461.

It is an arithmetic number, because the mean of its divisors is an integer number (229515591).

Almost surely, 2^916367981 is an apocalyptic number.

It is an amenable number.

916367981 is a deficient number, since it is larger than the sum of its proper divisors (1694383).

916367981 is a wasteful number, since it uses less digits than its factorization.

916367981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1694382.

The product of its digits is 489888, while the sum is 50.

The square root of 916367981 is about 30271.5705076562. The cubic root of 916367981 is about 971.3072610534.

The spelling of 916367981 in words is "nine hundred sixteen million, three hundred sixty-seven thousand, nine hundred eighty-one".