21155235150 has 96 divisors (see below), whose sum is σ = 60003302400. Its totient is φ = 4831989120.

The previous prime is 21155235137. The next prime is 21155235163. The reversal of 21155235150 is 5153255112.

It is an interprime number because it is at equal distance from previous prime (21155235137) and next prime (21155235163).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1619947 + ... + 1632953.

It is an arithmetic number, because the mean of its divisors is an integer number (625034400).

Almost surely, 2^21155235150 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21155235150, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30001651200).

21155235150 is an abundant number, since it is smaller than the sum of its proper divisors (38848067250).

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

21155235150 is a wasteful number, since it uses less digits than its factorization.

21155235150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14578 (or 14573 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 30.

The spelling of 21155235150 in words is "twenty-one billion, one hundred fifty-five million, two hundred thirty-five thousand, one hundred fifty".