21127253790 has 64 divisors (see below), whose sum is σ = 52145358336. Its totient is φ = 5475929472.

The previous prime is 21127253753. The next prime is 21127253821. The reversal of 21127253790 is 9735272112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 108039 + ... + 232221.

It is an arithmetic number, because the mean of its divisors is an integer number (814771224).

Almost surely, 2^21127253790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21127253790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26072679168).

21127253790 is an abundant number, since it is smaller than the sum of its proper divisors (31018104546).

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

21127253790 is a wasteful number, since it uses less digits than its factorization.

21127253790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124353.

The product of its (nonzero) digits is 52920, while the sum is 39.

The spelling of 21127253790 in words is "twenty-one billion, one hundred twenty-seven million, two hundred fifty-three thousand, seven hundred ninety".