20455992138 has 8 divisors (see below), whose sum is σ = 40911984288. Its totient is φ = 6818664044.

The previous prime is 20455992077. The next prime is 20455992143. The reversal of 20455992138 is 83129955402.

It is a happy number.

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

20455992138 is an admirable number.

It is a super-2 number, since 2×20455992138² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1704666006 + ... + 1704666017.

It is an arithmetic number, because the mean of its divisors is an integer number (5113998036).

Almost surely, 2^20455992138 is an apocalyptic number.

20455992138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20455992138 is a wasteful number, since it uses less digits than its factorization.

20455992138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3409332028.

The product of its (nonzero) digits is 777600, while the sum is 48.

The spelling of 20455992138 in words is "twenty billion, four hundred fifty-five million, nine hundred ninety-two thousand, one hundred thirty-eight".