21333234531 has 8 divisors (see below), whose sum is σ = 32507785984. Its totient is φ = 12190419720.

The previous prime is 21333234521. The next prime is 21333234539. The reversal of 21333234531 is 13543233312.

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

It is not a de Polignac number, because 21333234531 - 2²³ = 21324845923 is a prime.

It is a super-2 number, since 2×21333234531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21333234539) 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, 507934135 + ... + 507934176.

It is an arithmetic number, because the mean of its divisors is an integer number (4063473248).

Almost surely, 2^21333234531 is an apocalyptic number.

21333234531 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21333234531 is a deficient number, since it is larger than the sum of its proper divisors (11174551453).

21333234531 is a wasteful number, since it uses less digits than its factorization.

21333234531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015868321.

The product of its digits is 19440, while the sum is 30.

Adding to 21333234531 its reverse (13543233312), we get a palindrome (34876467843).

The spelling of 21333234531 in words is "twenty-one billion, three hundred thirty-three million, two hundred thirty-four thousand, five hundred thirty-one".