20497929984 has 360 divisors, whose sum is σ = 70240016000. Its totient is φ = 5824161792.

The previous prime is 20497929967. The next prime is 20497929989. The reversal of 20497929984 is 48992979402.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20497929989) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 41077767 + ... + 41078265.

Almost surely, 2^20497929984 is an apocalyptic number.

20497929984 is a gapful number since it is divisible by the number (24) 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 20497929984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35120008000).

20497929984 is an abundant number, since it is smaller than the sum of its proper divisors (49742086016).

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

20497929984 is an equidigital number, since it uses as much as digits as its factorization.

20497929984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817 (or 794 counting only the distinct ones).

The product of its (nonzero) digits is 23514624, while the sum is 63.

The spelling of 20497929984 in words is "twenty billion, four hundred ninety-seven million, nine hundred twenty-nine thousand, nine hundred eighty-four".