215226391 has 2 divisors, whose sum is σ = 215226392. Its totient is φ = 215226390.

The previous prime is 215226379. The next prime is 215226419. The reversal of 215226391 is 193622512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 215226391 - 2¹⁵ = 215193623 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215226331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107613195 + 107613196.

It is an arithmetic number, because the mean of its divisors is an integer number (107613196).

Almost surely, 2^215226391 is an apocalyptic number.

215226391 is a deficient number, since it is larger than the sum of its proper divisors (1).

215226391 is an equidigital number, since it uses as much as digits as its factorization.

215226391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 31.

The square root of 215226391 is about 14670.5961364902. The cubic root of 215226391 is about 599.2828385109.

The spelling of 215226391 in words is "two hundred fifteen million, two hundred twenty-six thousand, three hundred ninety-one".