20137961 has 2 divisors, whose sum is σ = 20137962. Its totient is φ = 20137960.

The previous prime is 20137951. The next prime is 20137963. The reversal of 20137961 is 16973102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15960025 + 4177936 = 3995^2 + 2044^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20137961 is a prime.

It is a Sophie Germain prime.

Together with 20137963, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20137963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10068980 + 10068981.

It is an arithmetic number, because the mean of its divisors is an integer number (10068981).

Almost surely, 2^20137961 is an apocalyptic number.

It is an amenable number.

20137961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20137961 is an equidigital number, since it uses as much as digits as its factorization.

20137961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 20137961 is about 4487.5339553033. The cubic root of 20137961 is about 272.0644716333.

The spelling of 20137961 in words is "twenty million, one hundred thirty-seven thousand, nine hundred sixty-one".