21438717040557 has 12 divisors (see below), whose sum is σ = 30967468440480. Its totient is φ = 14292278312328.

The previous prime is 21438717040457. The next prime is 21438717040561. The reversal of 21438717040557 is 75504071783412.

21438717040557 is a `hidden beast` number, since 2 + 1 + 4 + 3 + 87 + 1 + 7 + 0 + 4 + 0 + 557 = 666.

It is not a de Polignac number, because 21438717040557 - 2¹⁰ = 21438717039533 is a prime.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21438717040357) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15961563 + ... + 17252504.

It is an arithmetic number, because the mean of its divisors is an integer number (2580622370040).

Almost surely, 2^{21438717040557} is an apocalyptic number.

It is an amenable number.

21438717040557 is a deficient number, since it is larger than the sum of its proper divisors (9528751399923).

21438717040557 is a wasteful number, since it uses less digits than its factorization.

21438717040557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33285792 (or 33285789 counting only the distinct ones).

The product of its (nonzero) digits is 6585600, while the sum is 54.

The spelling of 21438717040557 in words is "twenty-one trillion, four hundred thirty-eight billion, seven hundred seventeen million, forty thousand, five hundred fifty-seven".