21937151 has 2 divisors, whose sum is σ = 21937152. Its totient is φ = 21937150.

The previous prime is 21937141. The next prime is 21937159. The reversal of 21937151 is 15173912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21937151 - 2⁶ = 21937087 is a prime.

It is equal to p_1385543 and since 21937151 and 1385543 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21937159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10968575 + 10968576.

It is an arithmetic number, because the mean of its divisors is an integer number (10968576).

Almost surely, 2^21937151 is an apocalyptic number.

21937151 is a deficient number, since it is larger than the sum of its proper divisors (1).

21937151 is an equidigital number, since it uses as much as digits as its factorization.

21937151 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1890, while the sum is 29.

The square root of 21937151 is about 4683.7112421668. The cubic root of 21937151 is about 279.9368522561.

The spelling of 21937151 in words is "twenty-one million, nine hundred thirty-seven thousand, one hundred fifty-one".