20121244400 has 60 divisors (see below), whose sum is σ = 49900716864. Its totient is φ = 7788864000.

The previous prime is 20121244379. The next prime is 20121244433. The reversal of 20121244400 is 444212102.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 798941 + ... + 823740.

Almost surely, 2^20121244400 is an apocalyptic number.

20121244400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121244400 is an abundant number, since it is smaller than the sum of its proper divisors (29779472464).

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

20121244400 is a wasteful number, since it uses less digits than its factorization.

20121244400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1622730 (or 1622719 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 20121244400 its reverse (444212102), we get a palindrome (20565456502).

The spelling of 20121244400 in words is "twenty billion, one hundred twenty-one million, two hundred forty-four thousand, four hundred".