21264685838 has 8 divisors (see below), whose sum is σ = 34796758680. Its totient is φ = 9665766280.

The previous prime is 21264685837. The next prime is 21264685853. The reversal of 21264685838 is 83858646212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21264685838.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21264685831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 483288293 + ... + 483288336.

It is an arithmetic number, because the mean of its divisors is an integer number (4349594835).

Almost surely, 2^21264685838 is an apocalyptic number.

21264685838 is a deficient number, since it is larger than the sum of its proper divisors (13532072842).

21264685838 is a wasteful number, since it uses less digits than its factorization.

21264685838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966576642.

The product of its digits is 4423680, while the sum is 53.

The spelling of 21264685838 in words is "twenty-one billion, two hundred sixty-four million, six hundred eighty-five thousand, eight hundred thirty-eight".