21838425815381 has 32 divisors (see below), whose sum is σ = 25158874718208. Its totient is φ = 18568615374720.

The previous prime is 21838425815341. The next prime is 21838425815407. The reversal of 21838425815381 is 18351852483812.

It is a cyclic number.

It is not a de Polignac number, because 21838425815381 - 2¹⁰ = 21838425814357 is a prime.

It is a super-2 number, since 2×21838425815381² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21838425815381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21838425815341) 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, 1380685385 + ... + 1380701201.

It is an arithmetic number, because the mean of its divisors is an integer number (786214834944).

Almost surely, 2^{21838425815381} is an apocalyptic number.

It is an amenable number.

21838425815381 is a deficient number, since it is larger than the sum of its proper divisors (3320448902827).

21838425815381 is a wasteful number, since it uses less digits than its factorization.

21838425815381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18201.

The product of its digits is 14745600, while the sum is 59.

The spelling of 21838425815381 in words is "twenty-one trillion, eight hundred thirty-eight billion, four hundred twenty-five million, eight hundred fifteen thousand, three hundred eighty-one".