21870745600 has 144 divisors (see below), whose sum is σ = 59157385560. Its totient is φ = 7952793600.

The previous prime is 21870745543. The next prime is 21870745601. The reversal of 21870745600 is 654707812.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21870745601) 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, 543784 + ... + 582616.

Almost surely, 2^21870745600 is an apocalyptic number.

21870745600 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 21870745600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29578692780).

21870745600 is an abundant number, since it is smaller than the sum of its proper divisors (37286639960).

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

21870745600 is a wasteful number, since it uses less digits than its factorization.

21870745600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38876 (or 38851 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 40.

The spelling of 21870745600 in words is "twenty-one billion, eight hundred seventy million, seven hundred forty-five thousand, six hundred".