20985937 has 16 divisors (see below), whose sum is σ = 26121600. Its totient is φ = 16450560.

The previous prime is 20985911. The next prime is 20985953. The reversal of 20985937 is 73958902.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-20985937 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20985893 and 20985902.

It is not an unprimeable number, because it can be changed into a prime (20985997) 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, 1137 + ... + 6577.

It is an arithmetic number, because the mean of its divisors is an integer number (1632600).

Almost surely, 2^20985937 is an apocalyptic number.

It is an amenable number.

20985937 is a deficient number, since it is larger than the sum of its proper divisors (5135663).

20985937 is a wasteful number, since it uses less digits than its factorization.

20985937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5496.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 20985937 is about 4581.0410388906. The cubic root of 20985937 is about 275.8308185672.

The spelling of 20985937 in words is "twenty million, nine hundred eighty-five thousand, nine hundred thirty-seven".