215913481 has 32 divisors (see below), whose sum is σ = 272719872. Its totient is φ = 166682880.

The previous prime is 215913479. The next prime is 215913491. The reversal of 215913481 is 184319512.

It is not a de Polignac number, because 215913481 - 2¹ = 215913479 is a prime.

It is a super-2 number, since 2×215913481² = 93237262555074722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215913431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 394450 + ... + 394996.

It is an arithmetic number, because the mean of its divisors is an integer number (8522496).

Almost surely, 2^215913481 is an apocalyptic number.

It is an amenable number.

215913481 is a deficient number, since it is larger than the sum of its proper divisors (56806391).

215913481 is a wasteful number, since it uses less digits than its factorization.

215913481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709.

The product of its digits is 8640, while the sum is 34.

The square root of 215913481 is about 14693.9947257375. The cubic root of 215913481 is about 599.9198791164.

The spelling of 215913481 in words is "two hundred fifteen million, nine hundred thirteen thousand, four hundred eighty-one".