20988986990 has 16 divisors (see below), whose sum is σ = 37789400880. Its totient is φ = 8393544960.

The previous prime is 20988986989. The next prime is 20988987001. The reversal of 20988986990 is 9968988902.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20988986990.

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, 212876 + ... + 295455.

It is an arithmetic number, because the mean of its divisors is an integer number (2361837555).

Almost surely, 2^20988986990 is an apocalyptic number.

20988986990 is a deficient number, since it is larger than the sum of its proper divisors (16800413890).

20988986990 is a wasteful number, since it uses less digits than its factorization.

20988986990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512467.

The product of its (nonzero) digits is 40310784, while the sum is 68.

The spelling of 20988986990 in words is "twenty billion, nine hundred eighty-eight million, nine hundred eighty-six thousand, nine hundred ninety".