21144132231 has 16 divisors (see below), whose sum is σ = 29820915456. Its totient is φ = 13298510016.

The previous prime is 21144132179. The next prime is 21144132241. The reversal of 21144132231 is 13223144112.

It is not a de Polignac number, because 21144132231 - 2⁶ = 21144132167 is a prime.

It is a super-2 number, since 2×21144132231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144132241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2093845 + ... + 2103918.

It is an arithmetic number, because the mean of its divisors is an integer number (1863807216).

Almost surely, 2^21144132231 is an apocalyptic number.

21144132231 is a deficient number, since it is larger than the sum of its proper divisors (8676783225).

21144132231 is a wasteful number, since it uses less digits than its factorization.

21144132231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4197862.

The product of its digits is 1152, while the sum is 24.

Adding to 21144132231 its reverse (13223144112), we get a palindrome (34367276343).

The spelling of 21144132231 in words is "twenty-one billion, one hundred forty-four million, one hundred thirty-two thousand, two hundred thirty-one".