21672261504 has 320 divisors, whose sum is σ = 69979140000. Its totient is φ = 6631096320.

The previous prime is 21672261491. The next prime is 21672261511. The reversal of 21672261504 is 40516227612.

It is a happy number.

21672261504 is a `hidden beast` number, since 2 + 16 + 7 + 22 + 615 + 0 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7224997 + ... + 7227995.

Almost surely, 2^21672261504 is an apocalyptic number.

21672261504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21672261504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34989570000).

21672261504 is an abundant number, since it is smaller than the sum of its proper divisors (48306878496).

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

21672261504 is a wasteful number, since it uses less digits than its factorization.

21672261504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3083 (or 3062 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The spelling of 21672261504 in words is "twenty-one billion, six hundred seventy-two million, two hundred sixty-one thousand, five hundred four".