215994390 has 16 divisors (see below), whose sum is σ = 518386608. Its totient is φ = 57598496.

The previous prime is 215994379. The next prime is 215994431. The reversal of 215994390 is 93499512.

215994390 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×215994390² = 93307153022944200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3599877 + ... + 3599936.

It is an arithmetic number, because the mean of its divisors is an integer number (32399163).

Almost surely, 2^215994390 is an apocalyptic number.

215994390 is an abundant number, since it is smaller than the sum of its proper divisors (302392218).

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

215994390 is a wasteful number, since it uses less digits than its factorization.

215994390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7199823.

The product of its (nonzero) digits is 87480, while the sum is 42.

The square root of 215994390 is about 14696.7475993840. The cubic root of 215994390 is about 599.9948055106.

The spelling of 215994390 in words is "two hundred fifteen million, nine hundred ninety-four thousand, three hundred ninety".