21896739 has 12 divisors (see below), whose sum is σ = 32101576. Its totient is φ = 14379552.

The previous prime is 21896717. The next prime is 21896767. The reversal of 21896739 is 93769812.

It is a de Polignac number, because none of the positive numbers 2^k-21896739 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21896694 and 21896703.

It is not an unprimeable number, because it can be changed into a prime (21896779) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17554 + ... + 18759.

Almost surely, 2^21896739 is an apocalyptic number.

21896739 is a deficient number, since it is larger than the sum of its proper divisors (10204837).

21896739 is a wasteful number, since it uses less digits than its factorization.

21896739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36386 (or 36383 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 21896739 is about 4679.3951532223. The cubic root of 21896739 is about 279.7648493389.

The spelling of 21896739 in words is "twenty-one million, eight hundred ninety-six thousand, seven hundred thirty-nine".