21838518505390 has 32 divisors (see below), whose sum is σ = 41378848727040. Its totient is φ = 8275528490400.

The previous prime is 21838518505369. The next prime is 21838518505411. The reversal of 21838518505390 is 9350581583812.

It is an interprime number because it is at equal distance from previous prime (21838518505369) and next prime (21838518505411).

It is a super-2 number, since 2×21838518505390² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12815635 + ... + 14419345.

It is an arithmetic number, because the mean of its divisors is an integer number (1293089022720).

Almost surely, 2^{21838518505390} is an apocalyptic number.

21838518505390 is a deficient number, since it is larger than the sum of its proper divisors (19540330221650).

21838518505390 is a wasteful number, since it uses less digits than its factorization.

21838518505390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1675408.

The product of its (nonzero) digits is 10368000, while the sum is 58.

The spelling of 21838518505390 in words is "twenty-one trillion, eight hundred thirty-eight billion, five hundred eighteen million, five hundred five thousand, three hundred ninety".