21253054243400 has 96 divisors (see below), whose sum is σ = 56502559021440. Its totient is φ = 7282870133760.

The previous prime is 21253054243319. The next prime is 21253054243403. The reversal of 21253054243400 is 434245035212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is not an unprimeable number, because it can be changed into a prime (21253054243403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1430324 + ... + 6674723.

It is an arithmetic number, because the mean of its divisors is an integer number (588568323140).

Almost surely, 2^{21253054243400} is an apocalyptic number.

21253054243400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21253054243400 is an abundant number, since it is smaller than the sum of its proper divisors (35249504778040).

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

21253054243400 is a wasteful number, since it uses less digits than its factorization.

21253054243400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8106943 (or 8106934 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 35.

Adding to 21253054243400 its reverse (434245035212), we get a palindrome (21687299278612).

The spelling of 21253054243400 in words is "twenty-one trillion, two hundred fifty-three billion, fifty-four million, two hundred forty-three thousand, four hundred".