21915298 has 12 divisors (see below), whose sum is σ = 33384582. Its totient is φ = 10789680.

The previous prime is 21915293. The next prime is 21915317. The reversal of 21915298 is 89251912.

It can be written as a sum of positive squares in only one way, i.e., 21372129 + 543169 = 4623^2 + 737^2 .

It is not an unprimeable number, because it can be changed into a prime (21915293) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7758 + ... + 10198.

Almost surely, 2^21915298 is an apocalyptic number.

21915298 is a deficient number, since it is larger than the sum of its proper divisors (11469284).

21915298 is an equidigital number, since it uses as much as digits as its factorization.

21915298 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2577 (or 2510 counting only the distinct ones).

The product of its digits is 12960, while the sum is 37.

The square root of 21915298 is about 4681.3777886430. The cubic root of 21915298 is about 279.8438670353.

The spelling of 21915298 in words is "twenty-one million, nine hundred fifteen thousand, two hundred ninety-eight".