21123010002 has 16 divisors (see below), whose sum is σ = 42876558432. Its totient is φ = 6935913600.

The previous prime is 21123009991. The next prime is 21123010003. The reversal of 21123010002 is 20001032112.

It is a self number, because there is not a number n which added to its sum of digits gives 21123010002.

It is not an unprimeable number, because it can be changed into a prime (21123010003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26271999 + ... + 26272802.

It is an arithmetic number, because the mean of its divisors is an integer number (2679784902).

Almost surely, 2^21123010002 is an apocalyptic number.

21123010002 is an abundant number, since it is smaller than the sum of its proper divisors (21753548430).

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

21123010002 is a wasteful number, since it uses less digits than its factorization.

21123010002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52544873.

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

Adding to 21123010002 its reverse (20001032112), we get a palindrome (41124042114).

The spelling of 21123010002 in words is "twenty-one billion, one hundred twenty-three million, ten thousand, two".