21139909127920 has 320 divisors, whose sum is σ = 54969512868864. Its totient is φ = 7496041512960.

The previous prime is 21139909127863. The next prime is 21139909127963. The reversal of 21139909127920 is 2972190993112.

It is a happy number.

21139909127920 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7282089189 + ... + 7282092091.

Almost surely, 2^{21139909127920} is an apocalyptic number.

21139909127920 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 21139909127920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27484756434432).

21139909127920 is an abundant number, since it is smaller than the sum of its proper divisors (33829603740944).

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

21139909127920 is a wasteful number, since it uses less digits than its factorization.

21139909127920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4200 (or 4194 counting only the distinct ones).

The product of its (nonzero) digits is 1102248, while the sum is 55.

The spelling of 21139909127920 in words is "twenty-one trillion, one hundred thirty-nine billion, nine hundred nine million, one hundred twenty-seven thousand, nine hundred twenty".