21232121231 has 8 divisors (see below), whose sum is σ = 21536620704. Its totient is φ = 20927773440.

The previous prime is 21232121213. The next prime is 21232121249. The reversal of 21232121231 is 13212123212.

It is an interprime number because it is at equal distance from previous prime (21232121213) and next prime (21232121249).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21232121231 - 2⁶ = 21232121167 is a prime.

It is a super-2 number, since 2×21232121231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232121201) 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, 260771 + ... + 332363.

It is an arithmetic number, because the mean of its divisors is an integer number (2692077588).

Almost surely, 2^21232121231 is an apocalyptic number.

21232121231 is a deficient number, since it is larger than the sum of its proper divisors (304499473).

21232121231 is an equidigital number, since it uses as much as digits as its factorization.

21232121231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75841.

The product of its digits is 288, while the sum is 20.

Adding to 21232121231 its reverse (13212123212), we get a palindrome (34444244443).

The spelling of 21232121231 in words is "twenty-one billion, two hundred thirty-two million, one hundred twenty-one thousand, two hundred thirty-one".