21131330375 has 16 divisors (see below), whose sum is σ = 26519257440. Its totient is φ = 16810604800.

The previous prime is 21131330371. The next prime is 21131330413. The reversal of 21131330375 is 57303313112.

It is not a de Polignac number, because 21131330375 - 2² = 21131330371 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131330371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 449834 + ... + 494583.

It is an arithmetic number, because the mean of its divisors is an integer number (1657453590).

Almost surely, 2^21131330375 is an apocalyptic number.

21131330375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21131330375 is a deficient number, since it is larger than the sum of its proper divisors (5387927065).

21131330375 is an equidigital number, since it uses as much as digits as its factorization.

21131330375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 944611 (or 944601 counting only the distinct ones).

The product of its (nonzero) digits is 5670, while the sum is 29.

Adding to 21131330375 its reverse (57303313112), we get a palindrome (78434643487).

The spelling of 21131330375 in words is "twenty-one billion, one hundred thirty-one million, three hundred thirty thousand, three hundred seventy-five".