215430813 has 16 divisors (see below), whose sum is σ = 343707840. Its totient is φ = 132572592.

The previous prime is 215430779. The next prime is 215430823. The reversal of 215430813 is 318034512.

It is a happy number.

215430813 is a `hidden beast` number, since 215 + 430 + 8 + 13 = 666.

It is not a de Polignac number, because 215430813 - 2²⁰ = 214382237 is a prime.

It is a super-3 number, since 3×215430813³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215430823) 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 15 ways as a sum of consecutive naturals, for example, 306531 + ... + 307232.

It is an arithmetic number, because the mean of its divisors is an integer number (21481740).

Almost surely, 2^215430813 is an apocalyptic number.

It is an amenable number.

215430813 is a deficient number, since it is larger than the sum of its proper divisors (128277027).

215430813 is a wasteful number, since it uses less digits than its factorization.

215430813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 613785 (or 613779 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 215430813 is about 14677.5615481591. The cubic root of 215430813 is about 599.4725113955.

The spelling of 215430813 in words is "two hundred fifteen million, four hundred thirty thousand, eight hundred thirteen".