20972141 has 2 divisors, whose sum is σ = 20972142. Its totient is φ = 20972140.

The previous prime is 20972137. The next prime is 20972167. The reversal of 20972141 is 14127902.

It is an a-pointer prime, because the next prime (20972167) can be obtained adding 20972141 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20967241 + 4900 = 4579^2 + 70^2 .

It is a cyclic number.

It is not a de Polignac number, because 20972141 - 2² = 20972137 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20972141.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20972111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10486070 + 10486071.

It is an arithmetic number, because the mean of its divisors is an integer number (10486071).

Almost surely, 2^20972141 is an apocalyptic number.

It is an amenable number.

20972141 is a deficient number, since it is larger than the sum of its proper divisors (1).

20972141 is an equidigital number, since it uses as much as digits as its factorization.

20972141 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 20972141 is about 4579.5350200648. The cubic root of 20972141 is about 275.7703622698.

The spelling of 20972141 in words is "twenty million, nine hundred seventy-two thousand, one hundred forty-one".