20909134400 has 672 divisors, whose sum is σ = 68793311232. Its totient is φ = 6062284800.

The previous prime is 20909134399. The next prime is 20909134429. The reversal of 20909134400 is 443190902.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 133179122 + ... + 133179278.

Almost surely, 2^20909134400 is an apocalyptic number.

20909134400 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 20909134400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34396655616).

20909134400 is an abundant number, since it is smaller than the sum of its proper divisors (47884176832).

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

20909134400 is a wasteful number, since it uses less digits than its factorization.

20909134400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 252 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The spelling of 20909134400 in words is "twenty billion, nine hundred nine million, one hundred thirty-four thousand, four hundred".