215572649 has 2 divisors, whose sum is σ = 215572650. Its totient is φ = 215572648.

The previous prime is 215572633. The next prime is 215572661. The reversal of 215572649 is 946275512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175377049 + 40195600 = 13243^2 + 6340^2 .

It is a cyclic number.

It is not a de Polignac number, because 215572649 - 2⁴ = 215572633 is a prime.

It is not a weakly prime, because it can be changed into another prime (215572549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107786324 + 107786325.

It is an arithmetic number, because the mean of its divisors is an integer number (107786325).

Almost surely, 2^215572649 is an apocalyptic number.

It is an amenable number.

215572649 is a deficient number, since it is larger than the sum of its proper divisors (1).

215572649 is an equidigital number, since it uses as much as digits as its factorization.

215572649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 151200, while the sum is 41.

The square root of 215572649 is about 14682.3924821536. The cubic root of 215572649 is about 599.6040433844.

The spelling of 215572649 in words is "two hundred fifteen million, five hundred seventy-two thousand, six hundred forty-nine".