102111000021 has 24 divisors (see below), whose sum is σ = 164389230720. Its totient is φ = 60697558656.

The previous prime is 102111000007. The next prime is 102111000041. The reversal of 102111000021 is 120000111201.

It is a happy number.

It is not a de Polignac number, because 102111000021 - 2¹⁵ = 102110967253 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 102110999967 and 102111000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102111000041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17560045 + ... + 17565858.

It is an arithmetic number, because the mean of its divisors is an integer number (6849551280).

Almost surely, 2^102111000021 is an apocalyptic number.

It is an amenable number.

102111000021 is a deficient number, since it is larger than the sum of its proper divisors (62278230699).

102111000021 is a wasteful number, since it uses less digits than its factorization.

102111000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35125945 (or 35125942 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 102111000021 its reverse (120000111201), we get a palindrome (222111111222).

The spelling of 102111000021 in words is "one hundred two billion, one hundred eleven million, twenty-one", and thus it is an aban number.