20381999356 has 24 divisors (see below), whose sum is σ = 37059624000. Its totient is φ = 9796605504.

The previous prime is 20381999303. The next prime is 20381999369. The reversal of 20381999356 is 65399918302.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20381999297 and 20381999306.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 357076 + ... + 410203.

It is an arithmetic number, because the mean of its divisors is an integer number (1544151000).

Almost surely, 2^20381999356 is an apocalyptic number.

It is an amenable number.

20381999356 is a deficient number, since it is larger than the sum of its proper divisors (16677624644).

20381999356 is a wasteful number, since it uses less digits than its factorization.

20381999356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 767541 (or 767539 counting only the distinct ones).

The product of its (nonzero) digits is 3149280, while the sum is 55.

The spelling of 20381999356 in words is "twenty billion, three hundred eighty-one million, nine hundred ninety-nine thousand, three hundred fifty-six".