21112121310 has 32 divisors (see below), whose sum is σ = 57907533312. Its totient is φ = 4825627680.

The previous prime is 21112121269. The next prime is 21112121351. The reversal of 21112121310 is 1312121112.

It is an interprime number because it is at equal distance from previous prime (21112121269) and next prime (21112121351).

It is a super-2 number, since 2×21112121310² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21112121310.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50266746 + ... + 50267165.

It is an arithmetic number, because the mean of its divisors is an integer number (1809610416).

Almost surely, 2^21112121310 is an apocalyptic number.

21112121310 is an abundant number, since it is smaller than the sum of its proper divisors (36795412002).

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

21112121310 is a wasteful number, since it uses less digits than its factorization.

21112121310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100533928.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21112121310 its reverse (1312121112), we get a palindrome (22424242422).

The spelling of 21112121310 in words is "twenty-one billion, one hundred twelve million, one hundred twenty-one thousand, three hundred ten".