40115683521 has 9 divisors (see below), whose sum is σ = 57945744129. Its totient is φ = 26743388436.

The previous prime is 40115683483. The next prime is 40115683529. The reversal of 40115683521 is 12538651104.

The square root of 40115683521 is 200289.

It is a perfect power (a square), and thus also a powerful number.

40115683521 is a `hidden beast` number, since 4 + 0 + 1 + 1 + 56 + 83 + 521 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 40115683521 - 2³³ = 31525748929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40115683529) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 567486 + ... + 634248.

Almost surely, 2^40115683521 is an apocalyptic number.

40115683521 is the 200289-th square number.

40115683521 is the 100145-th centered octagonal number.

It is an amenable number.

40115683521 is a deficient number, since it is larger than the sum of its proper divisors (17830060608).

40115683521 is an frugal number, since it uses more digits than its factorization.

40115683521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133532 (or 66766 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

Multiplying 40115683521 by its sum of digits (36), we get a square (1444164606756 = 1201734²).

The spelling of 40115683521 in words is "forty billion, one hundred fifteen million, six hundred eighty-three thousand, five hundred twenty-one".