215409236540 has 48 divisors (see below), whose sum is σ = 473695423488. Its totient is φ = 82126169664.

The previous prime is 215409236489. The next prime is 215409236551. The reversal of 215409236540 is 45632904512.

It is a super-2 number, since 2×215409236540² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 697172 + ... + 957531.

It is an arithmetic number, because the mean of its divisors is an integer number (9868654656).

Almost surely, 2^215409236540 is an apocalyptic number.

215409236540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215409236540 is an abundant number, since it is smaller than the sum of its proper divisors (258286186948).

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

215409236540 is a wasteful number, since it uses less digits than its factorization.

215409236540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1655018 (or 1655016 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 41.

The spelling of 215409236540 in words is "two hundred fifteen billion, four hundred nine million, two hundred thirty-six thousand, five hundred forty".