21618170680 has 16 divisors (see below), whose sum is σ = 48640884120. Its totient is φ = 8647268256.

The previous prime is 21618170677. The next prime is 21618170699. The reversal of 21618170680 is 8607181612.

It is a super-2 number, since 2×21618170680² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 540454267 = 21618170680 / (2 + 1 + 6 + 1 + 8 + 1 + 7 + 0 + 6 + 8 + 0).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270227094 + ... + 270227173.

Almost surely, 2^21618170680 is an apocalyptic number.

21618170680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21618170680 is an abundant number, since it is smaller than the sum of its proper divisors (27022713440).

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

21618170680 is a wasteful number, since it uses less digits than its factorization.

21618170680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540454278 (or 540454274 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 40.

The spelling of 21618170680 in words is "twenty-one billion, six hundred eighteen million, one hundred seventy thousand, six hundred eighty".