215985136240 has 80 divisors (see below), whose sum is σ = 503505952128. Its totient is φ = 86163775488.

The previous prime is 215985136219. The next prime is 215985136243. The reversal of 215985136240 is 42631589512.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×215985136240² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215985136243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59383702 + ... + 59387338.

Almost surely, 2^215985136240 is an apocalyptic number.

215985136240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215985136240 is an abundant number, since it is smaller than the sum of its proper divisors (287520815888).

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

215985136240 is a wasteful number, since it uses less digits than its factorization.

215985136240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5426 (or 5420 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 46.

The spelling of 215985136240 in words is "two hundred fifteen billion, nine hundred eighty-five million, one hundred thirty-six thousand, two hundred forty".