19972151 has 2 divisors, whose sum is σ = 19972152. Its totient is φ = 19972150.

The previous prime is 19972111. The next prime is 19972157. The reversal of 19972151 is 15127991.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19972151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19972157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9986075 + 9986076.

It is an arithmetic number, because the mean of its divisors is an integer number (9986076).

Almost surely, 2^19972151 is an apocalyptic number.

19972151 is a deficient number, since it is larger than the sum of its proper divisors (1).

19972151 is an equidigital number, since it uses as much as digits as its factorization.

19972151 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5670, while the sum is 35.

The square root of 19972151 is about 4469.0212575015. The cubic root of 19972151 is about 271.3157134424.

The spelling of 19972151 in words is "nineteen million, nine hundred seventy-two thousand, one hundred fifty-one".