21293906480 has 640 divisors, whose sum is σ = 68567040000. Its totient is φ = 6076062720.

The previous prime is 21293906467. The next prime is 21293906489. The reversal of 21293906480 is 8460939212.

It is a super-3 number, since 3×21293906480³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is not an unprimeable number, because it can be changed into a prime (21293906489) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 269543081 + ... + 269543159.

It is an arithmetic number, because the mean of its divisors is an integer number (107136000).

Almost surely, 2^21293906480 is an apocalyptic number.

21293906480 is a gapful number since it is divisible by the number (20) 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 21293906480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34283520000).

21293906480 is an abundant number, since it is smaller than the sum of its proper divisors (47273133520).

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

21293906480 is a wasteful number, since it uses less digits than its factorization.

21293906480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 44.

The spelling of 21293906480 in words is "twenty-one billion, two hundred ninety-three million, nine hundred six thousand, four hundred eighty".