215940249 has 24 divisors (see below), whose sum is σ = 369678400. Its totient is φ = 123393456.

The previous prime is 215940247. The next prime is 215940271. The reversal of 215940249 is 942049512.

215940249 is a `hidden beast` number, since 21 + 594 + 0 + 2 + 49 = 666.

It is not a de Polignac number, because 215940249 - 2¹ = 215940247 is a prime.

It is a super-2 number, since 2×215940249² = 93260382276364002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215940247) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61774 + ... + 65175.

Almost surely, 2^215940249 is an apocalyptic number.

It is an amenable number.

215940249 is a deficient number, since it is larger than the sum of its proper divisors (153738151).

215940249 is an equidigital number, since it uses as much as digits as its factorization.

215940249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126971 (or 126959 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 215940249 is about 14694.9055458006. The cubic root of 215940249 is about 599.9446698978.

The spelling of 215940249 in words is "two hundred fifteen million, nine hundred forty thousand, two hundred forty-nine".