21155127630 has 384 divisors, whose sum is σ = 66912998400. Its totient is φ = 4179382272.

The previous prime is 21155127629. The next prime is 21155127661. The reversal of 21155127630 is 3672155112.

It is a junction number, because it is equal to n+sod(n) for n = 21155127591 and 21155127600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 92380356 + ... + 92380584.

It is an arithmetic number, because the mean of its divisors is an integer number (174252600).

Almost surely, 2^21155127630 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21155127630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33456499200).

21155127630 is an abundant number, since it is smaller than the sum of its proper divisors (45757870770).

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

21155127630 is a wasteful number, since it uses less digits than its factorization.

21155127630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 33.

It can be divided in two parts, 21155 and 127630, that added together give a triangular number (148785 = T₅₄₅).

The spelling of 21155127630 in words is "twenty-one billion, one hundred fifty-five million, one hundred twenty-seven thousand, six hundred thirty".