21850637 has 2 divisors, whose sum is σ = 21850638. Its totient is φ = 21850636.

The previous prime is 21850607. The next prime is 21850679. The reversal of 21850637 is 73605812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21799561 + 51076 = 4669^2 + 226^2 .

It is a cyclic number.

It is not a de Polignac number, because 21850637 - 2⁶ = 21850573 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21850607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10925318 + 10925319.

It is an arithmetic number, because the mean of its divisors is an integer number (10925319).

Almost surely, 2^21850637 is an apocalyptic number.

It is an amenable number.

21850637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21850637 is an equidigital number, since it uses as much as digits as its factorization.

21850637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 21850637 is about 4674.4664936226. The cubic root of 21850637 is about 279.5683698323.

The spelling of 21850637 in words is "twenty-one million, eight hundred fifty thousand, six hundred thirty-seven".