102111221525 has 6 divisors (see below), whose sum is σ = 126617914722. Its totient is φ = 81688977200.

The previous prime is 102111221503. The next prime is 102111221533. The reversal of 102111221525 is 525122111201.

It can be written as a sum of positive squares in 3 ways, for example, as 6764898001 + 95346323524 = 82249^2 + 308782^2 .

It is not a de Polignac number, because 102111221525 - 2⁶ = 102111221461 is a prime.

It is a super-2 number, since 2×102111221525² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 102111221525.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2042224406 + ... + 2042224455.

It is an arithmetic number, because the mean of its divisors is an integer number (21102985787).

Almost surely, 2^102111221525 is an apocalyptic number.

It is an amenable number.

102111221525 is a deficient number, since it is larger than the sum of its proper divisors (24506693197).

102111221525 is an equidigital number, since it uses as much as digits as its factorization.

102111221525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4084448871 (or 4084448866 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 23.

Adding to 102111221525 its reverse (525122111201), we get a palindrome (627233332726).

The spelling of 102111221525 in words is "one hundred two billion, one hundred eleven million, two hundred twenty-one thousand, five hundred twenty-five".