20109697920 has 384 divisors, whose sum is σ = 75551767200. Its totient is φ = 4899225600.

The previous prime is 20109697897. The next prime is 20109697921. The reversal of 20109697920 is 2979690102.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20109697921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7561551 + ... + 7564209.

Almost surely, 2^20109697920 is an apocalyptic number.

20109697920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20109697920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37775883600).

20109697920 is an abundant number, since it is smaller than the sum of its proper divisors (55442069280).

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

20109697920 is a wasteful number, since it uses less digits than its factorization.

20109697920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2798 (or 2783 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The spelling of 20109697920 in words is "twenty billion, one hundred nine million, six hundred ninety-seven thousand, nine hundred twenty".