215898901 has 2 divisors, whose sum is σ = 215898902. Its totient is φ = 215898900.

The previous prime is 215898899. The next prime is 215898941. The reversal of 215898901 is 109898512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 141491025 + 74407876 = 11895^2 + 8626^2 .

It is a cyclic number.

It is not a de Polignac number, because 215898901 - 2¹ = 215898899 is a prime.

It is a super-2 number, since 2×215898901² = 93224670906015602, which contains 22 as substring.

Together with 215898899, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215898941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107949450 + 107949451.

It is an arithmetic number, because the mean of its divisors is an integer number (107949451).

Almost surely, 2^215898901 is an apocalyptic number.

It is an amenable number.

215898901 is a deficient number, since it is larger than the sum of its proper divisors (1).

215898901 is an equidigital number, since it uses as much as digits as its factorization.

215898901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 43.

The square root of 215898901 is about 14693.4985963180. The cubic root of 215898901 is about 599.9063752062.

The spelling of 215898901 in words is "two hundred fifteen million, eight hundred ninety-eight thousand, nine hundred one".