11457981 has 6 divisors (see below), whose sum is σ = 16550430. Its totient is φ = 7638648.

The previous prime is 11457973. The next prime is 11457997. The reversal of 11457981 is 18975411.

11457981 is a `hidden beast` number, since 1 + 1 + 4 + 579 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 9180900 + 2277081 = 3030^2 + 1509^2 .

It is not a de Polignac number, because 11457981 - 2³ = 11457973 is a prime.

It is a super-2 number, since 2×11457981² = 262570657192722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11457961) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 636546 + ... + 636563.

It is an arithmetic number, because the mean of its divisors is an integer number (2758405).

Almost surely, 2^11457981 is an apocalyptic number.

It is an amenable number.

11457981 is a deficient number, since it is larger than the sum of its proper divisors (5092449).

11457981 is a wasteful number, since it uses less digits than its factorization.

11457981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1273115 (or 1273112 counting only the distinct ones).

The product of its digits is 10080, while the sum is 36.

The square root of 11457981 is about 3384.9639584492. The cubic root of 11457981 is about 225.4426249836.

The spelling of 11457981 in words is "eleven million, four hundred fifty-seven thousand, nine hundred eighty-one".