21757113 has 16 divisors (see below), whose sum is σ = 36837760. Its totient is φ = 12432528.

The previous prime is 21757091. The next prime is 21757121. The reversal of 21757113 is 31175712.

It is a happy number.

It is not a de Polignac number, because 21757113 - 2⁶ = 21757049 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21757123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57370 + ... + 57747.

It is an arithmetic number, because the mean of its divisors is an integer number (2302360).

Almost surely, 2^21757113 is an apocalyptic number.

It is an amenable number.

21757113 is a deficient number, since it is larger than the sum of its proper divisors (15080647).

21757113 is a wasteful number, since it uses less digits than its factorization.

21757113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115133 (or 115127 counting only the distinct ones).

The product of its digits is 1470, while the sum is 27.

The square root of 21757113 is about 4664.4520578520. The cubic root of 21757113 is about 279.1689345723.

The spelling of 21757113 in words is "twenty-one million, seven hundred fifty-seven thousand, one hundred thirteen".