215606431 has 2 divisors, whose sum is σ = 215606432. Its totient is φ = 215606430.

The previous prime is 215606411. The next prime is 215606467. The reversal of 215606431 is 134606512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 215606431 - 2²¹ = 213509279 is a prime.

It is a super-2 number, since 2×215606431² = 92972266177115522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 215606431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215606411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107803215 + 107803216.

It is an arithmetic number, because the mean of its divisors is an integer number (107803216).

Almost surely, 2^215606431 is an apocalyptic number.

215606431 is a deficient number, since it is larger than the sum of its proper divisors (1).

215606431 is an equidigital number, since it uses as much as digits as its factorization.

215606431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 215606431 is about 14683.5428626745. The cubic root of 215606431 is about 599.6353627036.

The spelling of 215606431 in words is "two hundred fifteen million, six hundred six thousand, four hundred thirty-one".