20000399881 has 24 divisors (see below), whose sum is σ = 25659083520. Its totient is φ = 15253106880.

The previous prime is 20000399873. The next prime is 20000399893. The reversal of 20000399881 is 18899300002.

It is not a de Polignac number, because 20000399881 - 2³ = 20000399873 is a prime.

It is a super-2 number, since 2×20000399881² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (20000390881) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 211396 + ... + 291013.

It is an arithmetic number, because the mean of its divisors is an integer number (1069128480).

Almost surely, 2^20000399881 is an apocalyptic number.

It is an amenable number.

20000399881 is a deficient number, since it is larger than the sum of its proper divisors (5658683639).

20000399881 is a wasteful number, since it uses less digits than its factorization.

20000399881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502485 (or 502474 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

Adding to 20000399881 its reverse (18899300002), we get a palindrome (38899699883).

The spelling of 20000399881 in words is "twenty billion, three hundred ninety-nine thousand, eight hundred eighty-one".