21012120030 has 64 divisors (see below), whose sum is σ = 55031332608. Its totient is φ = 5092200960.

The previous prime is 21012119983. The next prime is 21012120047. The reversal of 21012120030 is 3002121012.

It is a junction number, because it is equal to n+sod(n) for n = 21012119988 and 21012120015.

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, 1243297 + ... + 1260083.

It is an arithmetic number, because the mean of its divisors is an integer number (859864572).

Almost surely, 2^21012120030 is an apocalyptic number.

21012120030 is an abundant number, since it is smaller than the sum of its proper divisors (34019212578).

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

21012120030 is a wasteful number, since it uses less digits than its factorization.

21012120030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20601.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21012120030 its reverse (3002121012), we get a palindrome (24014241042).

The spelling of 21012120030 in words is "twenty-one billion, twelve million, one hundred twenty thousand, thirty".