2121231525 has 48 divisors (see below), whose sum is σ = 4243906944. Its totient is φ = 912660480.

The previous prime is 2121231521. The next prime is 2121231533. The reversal of 2121231525 is 5251321212.

It is not a de Polignac number, because 2121231525 - 2² = 2121231521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121231495 and 2121231504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121231521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 109912 + ... + 127761.

It is an arithmetic number, because the mean of its divisors is an integer number (88414728).

Almost surely, 2^2121231525 is an apocalyptic number.

2121231525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2121231525 is an abundant number, since it is smaller than the sum of its proper divisors (2122675419).

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

2121231525 is a wasteful number, since it uses less digits than its factorization.

2121231525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237710 (or 237705 counting only the distinct ones).

The product of its digits is 1200, while the sum is 24.

The square root of 2121231525 is about 46056.8292981616. The cubic root of 2121231525 is about 1284.8803605046.

Adding to 2121231525 its reverse (5251321212), we get a palindrome (7372552737).

The spelling of 2121231525 in words is "two billion, one hundred twenty-one million, two hundred thirty-one thousand, five hundred twenty-five".