21461739 has 32 divisors (see below), whose sum is σ = 32175360. Its totient is φ = 12638592.

The previous prime is 21461731. The next prime is 21461747. The reversal of 21461739 is 93716412.

It is an interprime number because it is at equal distance from previous prime (21461731) and next prime (21461747).

It is not a de Polignac number, because 21461739 - 2³ = 21461731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21461731) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 154332 + ... + 154470.

It is an arithmetic number, because the mean of its divisors is an integer number (1005480).

Almost surely, 2^21461739 is an apocalyptic number.

21461739 is a deficient number, since it is larger than the sum of its proper divisors (10713621).

21461739 is a wasteful number, since it uses less digits than its factorization.

21461739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299.

The product of its digits is 9072, while the sum is 33.

The square root of 21461739 is about 4632.6816208326. The cubic root of 21461739 is about 277.8998440167.

The spelling of 21461739 in words is "twenty-one million, four hundred sixty-one thousand, seven hundred thirty-nine".