20989097460 has 240 divisors, whose sum is σ = 71548055040. Its totient is φ = 5131226880.

The previous prime is 20989097431. The next prime is 20989097497. The reversal of 20989097460 is 6479098902.

20989097460 is a `hidden beast` number, since 2 + 0 + 9 + 8 + 90 + 97 + 460 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 20989097397 and 20989097406.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 943182 + ... + 965178.

It is an arithmetic number, because the mean of its divisors is an integer number (298116896).

Almost surely, 2^20989097460 is an apocalyptic number.

20989097460 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 20989097460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35774027520).

20989097460 is an abundant number, since it is smaller than the sum of its proper divisors (50558957580).

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

20989097460 is a wasteful number, since it uses less digits than its factorization.

20989097460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22068 (or 22057 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 54.

The spelling of 20989097460 in words is "twenty billion, nine hundred eighty-nine million, ninety-seven thousand, four hundred sixty".