21123021031110 has 96 divisors (see below), whose sum is σ = 55275006346560. Its totient is φ = 5596386741504.

The previous prime is 21123021031097. The next prime is 21123021031183. The reversal of 21123021031110 is 1113012032112.

21123021031110 is a `hidden beast` number, since 2 + 112 + 30 + 210 + 311 + 1 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 158373031 + ... + 158506349.

It is an arithmetic number, because the mean of its divisors is an integer number (575781316110).

Almost surely, 2^{21123021031110} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21123021031110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27637503173280).

21123021031110 is an abundant number, since it is smaller than the sum of its proper divisors (34151985315450).

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

21123021031110 is a wasteful number, since it uses less digits than its factorization.

21123021031110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144702 (or 144699 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 21123021031110 its reverse (1113012032112), we get a palindrome (22236033063222).

The spelling of 21123021031110 in words is "twenty-one trillion, one hundred twenty-three billion, twenty-one million, thirty-one thousand, one hundred ten".