215211690 has 48 divisors (see below), whose sum is σ = 583884288. Its totient is φ = 54894048.

The previous prime is 215211677. The next prime is 215211691. The reversal of 215211690 is 96112512.

It is a super-2 number, since 2×215211690² = 92632143025312200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215211691) 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 in 23 ways as a sum of consecutive naturals, for example, 49914 + ... + 54053.

It is an arithmetic number, because the mean of its divisors is an integer number (12164256).

Almost surely, 2^215211690 is an apocalyptic number.

215211690 is an abundant number, since it is smaller than the sum of its proper divisors (368672598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

215211690 is a wasteful number, since it uses less digits than its factorization.

215211690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104003 (or 104000 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 215211690 is about 14670.0950917163. The cubic root of 215211690 is about 599.2691935647.

The spelling of 215211690 in words is "two hundred fifteen million, two hundred eleven thousand, six hundred ninety".