20139737 has 2 divisors, whose sum is σ = 20139738. Its totient is φ = 20139736.

The previous prime is 20139683. The next prime is 20139773. The reversal of 20139737 is 73793102.

Together with next prime (20139773) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10523536 + 9616201 = 3244^2 + 3101^2 .

It is a cyclic number.

It is not a de Polignac number, because 20139737 - 2⁶ = 20139673 is a prime.

It is not a weakly prime, because it can be changed into another prime (20139937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10069868 + 10069869.

It is an arithmetic number, because the mean of its divisors is an integer number (10069869).

Almost surely, 2^20139737 is an apocalyptic number.

It is an amenable number.

20139737 is a deficient number, since it is larger than the sum of its proper divisors (1).

20139737 is an equidigital number, since it uses as much as digits as its factorization.

20139737 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7938, while the sum is 32.

The square root of 20139737 is about 4487.7318324517. The cubic root of 20139737 is about 272.0724693364.

The spelling of 20139737 in words is "twenty million, one hundred thirty-nine thousand, seven hundred thirty-seven".