215639425 has 12 divisors (see below), whose sum is σ = 271161216. Its totient is φ = 170080400.

The previous prime is 215639419. The next prime is 215639429. The reversal of 215639425 is 524936512.

It is not a de Polignac number, because 215639425 - 2⁵ = 215639393 is a prime.

It is a super-2 number, since 2×215639425² = 93000723228661250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215639429) 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 11 ways as a sum of consecutive naturals, for example, 58969 + ... + 62518.

It is an arithmetic number, because the mean of its divisors is an integer number (22596768).

Almost surely, 2^215639425 is an apocalyptic number.

215639425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

215639425 is a deficient number, since it is larger than the sum of its proper divisors (55521791).

215639425 is a wasteful number, since it uses less digits than its factorization.

215639425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121568 (or 121563 counting only the distinct ones).

The product of its digits is 64800, while the sum is 37.

The square root of 215639425 is about 14684.6663223922. Note that the first 3 decimals coincide. The cubic root of 215639425 is about 599.6659483096.

The spelling of 215639425 in words is "two hundred fifteen million, six hundred thirty-nine thousand, four hundred twenty-five".