21319137 has 24 divisors (see below), whose sum is σ = 36726144. Its totient is φ = 11651904.

The previous prime is 21319127. The next prime is 21319169. The reversal of 21319137 is 73191312.

It is not a de Polignac number, because 21319137 - 2⁸ = 21318881 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21319137.

It is not an unprimeable number, because it can be changed into a prime (21319127) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5908 + ... + 8805.

It is an arithmetic number, because the mean of its divisors is an integer number (1530256).

Almost surely, 2^21319137 is an apocalyptic number.

It is an amenable number.

21319137 is a deficient number, since it is larger than the sum of its proper divisors (15407007).

21319137 is a wasteful number, since it uses less digits than its factorization.

21319137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14749 (or 14746 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 21319137 is about 4617.2650996017. The cubic root of 21319137 is about 277.2829761654.

The spelling of 21319137 in words is "twenty-one million, three hundred nineteen thousand, one hundred thirty-seven".