20722951 has 2 divisors, whose sum is σ = 20722952. Its totient is φ = 20722950.

The previous prime is 20722937. The next prime is 20722963. The reversal of 20722951 is 15922702.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20722951 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20722921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10361475 + 10361476.

It is an arithmetic number, because the mean of its divisors is an integer number (10361476).

Almost surely, 2^20722951 is an apocalyptic number.

20722951 is a deficient number, since it is larger than the sum of its proper divisors (1).

20722951 is an equidigital number, since it uses as much as digits as its factorization.

20722951 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 20722951 is about 4552.2468078961. The cubic root of 20722951 is about 274.6737773541.

The spelling of 20722951 in words is "twenty million, seven hundred twenty-two thousand, nine hundred fifty-one".