21574129 has 2 divisors, whose sum is σ = 21574130. Its totient is φ = 21574128.

The previous prime is 21574087. The next prime is 21574141. The reversal of 21574129 is 92147512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14137600 + 7436529 = 3760^2 + 2727^2 .

It is a cyclic number.

It is not a de Polignac number, because 21574129 - 2¹⁵ = 21541361 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21574129.

It is not a weakly prime, because it can be changed into another prime (21574199) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10787064 + 10787065.

It is an arithmetic number, because the mean of its divisors is an integer number (10787065).

Almost surely, 2^21574129 is an apocalyptic number.

It is an amenable number.

21574129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21574129 is an equidigital number, since it uses as much as digits as its factorization.

21574129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 31.

The square root of 21574129 is about 4644.7959050964. The cubic root of 21574129 is about 278.3840980549.

The spelling of 21574129 in words is "twenty-one million, five hundred seventy-four thousand, one hundred twenty-nine".