20631937 has 2 divisors, whose sum is σ = 20631938. Its totient is φ = 20631936.

The previous prime is 20631911. The next prime is 20631953. The reversal of 20631937 is 73913602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13535041 + 7096896 = 3679^2 + 2664^2 .

It is a cyclic number.

It is not a de Polignac number, because 20631937 - 2¹⁵ = 20599169 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20631899 and 20631908.

It is not a weakly prime, because it can be changed into another prime (20631907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10315968 + 10315969.

It is an arithmetic number, because the mean of its divisors is an integer number (10315969).

Almost surely, 2^20631937 is an apocalyptic number.

It is an amenable number.

20631937 is a deficient number, since it is larger than the sum of its proper divisors (1).

20631937 is an equidigital number, since it uses as much as digits as its factorization.

20631937 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6804, while the sum is 31.

The square root of 20631937 is about 4542.2392055021. The cubic root of 20631937 is about 274.2710701171.

The spelling of 20631937 in words is "twenty million, six hundred thirty-one thousand, nine hundred thirty-seven".