21375657498 has 64 divisors (see below), whose sum is σ = 47028465792. Its totient is φ = 6437283840.

The previous prime is 21375657493. The next prime is 21375657517. The reversal of 21375657498 is 89475657312.

It is a super-3 number, since 3×21375657498³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21375657493) 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 31 ways as a sum of consecutive naturals, for example, 731586 + ... + 760242.

It is an arithmetic number, because the mean of its divisors is an integer number (734819778).

Almost surely, 2^21375657498 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21375657498, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23514232896).

21375657498 is an abundant number, since it is smaller than the sum of its proper divisors (25652808294).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21375657498 is a wasteful number, since it uses less digits than its factorization.

21375657498 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28879.

The product of its digits is 12700800, while the sum is 57.

The spelling of 21375657498 in words is "twenty-one billion, three hundred seventy-five million, six hundred fifty-seven thousand, four hundred ninety-eight".