21474361920 has 896 divisors, whose sum is σ = 83760210432. Its totient is φ = 4600627200.

The previous prime is 21474361919. The next prime is 21474361921. The reversal of 21474361920 is 2916347412.

It is an interprime number because it is at equal distance from previous prime (21474361919) and next prime (21474361921).

It is a super-2 number, since 2×21474361920² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21474361921) 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, 352038690 + ... + 352038750.

Almost surely, 2^21474361920 is an apocalyptic number.

21474361920 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 21474361920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41880105216).

21474361920 is an abundant number, since it is smaller than the sum of its proper divisors (62285848512).

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

21474361920 is a wasteful number, since it uses less digits than its factorization.

21474361920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199 (or 189 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 39.

The spelling of 21474361920 in words is "twenty-one billion, four hundred seventy-four million, three hundred sixty-one thousand, nine hundred twenty".