21121432412 has 12 divisors (see below), whose sum is σ = 36973360536. Its totient is φ = 10557615120.

The previous prime is 21121432331. The next prime is 21121432433. The reversal of 21121432412 is 21423412112.

It is a super-2 number, since 2×21121432412² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 759914 + ... + 787217.

It is an arithmetic number, because the mean of its divisors is an integer number (3081113378).

Almost surely, 2^21121432412 is an apocalyptic number.

It is an amenable number.

21121432412 is a deficient number, since it is larger than the sum of its proper divisors (15851928124).

21121432412 is a wasteful number, since it uses less digits than its factorization.

21121432412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1550548 (or 1550546 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

Adding to 21121432412 its reverse (21423412112), we get a palindrome (42544844524).

The spelling of 21121432412 in words is "twenty-one billion, one hundred twenty-one million, four hundred thirty-two thousand, four hundred twelve".