20988699405 has 16 divisors (see below), whose sum is σ = 33914415744. Its totient is φ = 11083140800.

The previous prime is 20988699373. The next prime is 20988699469. The reversal of 20988699405 is 50499688902.

It is not a de Polignac number, because 20988699405 - 2⁵ = 20988699373 is a prime.

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, 6925449 + ... + 6928478.

It is an arithmetic number, because the mean of its divisors is an integer number (2119650984).

Almost surely, 2^20988699405 is an apocalyptic number.

It is an amenable number.

20988699405 is a deficient number, since it is larger than the sum of its proper divisors (12925716339).

20988699405 is a wasteful number, since it uses less digits than its factorization.

20988699405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13854036.

The product of its (nonzero) digits is 11197440, while the sum is 60.

It can be divided in two parts, 209886 and 99405, that added together give a triangular number (309291 = T₇₈₆).

The spelling of 20988699405 in words is "twenty billion, nine hundred eighty-eight million, six hundred ninety-nine thousand, four hundred five".