21988070400 has 264 divisors, whose sum is σ = 74454859584. Its totient is φ = 5719654400.

The previous prime is 21988070399. The next prime is 21988070407. The reversal of 21988070400 is 407088912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21988070407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3145309 + ... + 3152291.

Almost surely, 2^21988070400 is an apocalyptic number.

21988070400 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 21988070400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37227429792).

21988070400 is an abundant number, since it is smaller than the sum of its proper divisors (52466789184).

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

21988070400 is a wasteful number, since it uses less digits than its factorization.

21988070400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7057 (or 7034 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 39.

The spelling of 21988070400 in words is "twenty-one billion, nine hundred eighty-eight million, seventy thousand, four hundred".