21144332031 has 32 divisors (see below), whose sum is σ = 29002821120. Its totient is φ = 13697101824.

The previous prime is 21144331997. The next prime is 21144332057. The reversal of 21144332031 is 13023344112.

It is a happy number.

It is not a de Polignac number, because 21144332031 - 2⁷ = 21144331903 is a prime.

It is a super-2 number, since 2×21144332031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21144331992 and 21144332010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144332431) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17373535 + ... + 17374751.

It is an arithmetic number, because the mean of its divisors is an integer number (906338160).

Almost surely, 2^21144332031 is an apocalyptic number.

21144332031 is a deficient number, since it is larger than the sum of its proper divisors (7858489089).

21144332031 is a wasteful number, since it uses less digits than its factorization.

21144332031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2335.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21144332031 its reverse (13023344112), we get a palindrome (34167676143).

The spelling of 21144332031 in words is "twenty-one billion, one hundred forty-four million, three hundred thirty-two thousand, thirty-one".