21004245200000 has 384 divisors, whose sum is σ = 52858403720640. Its totient is φ = 8312855040000.

The previous prime is 21004245199991. The next prime is 21004245200017. The reversal of 21004245200000 is 254240012.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18060399419 + ... + 18060400581.

Almost surely, 2^{21004245200000} is an apocalyptic number.

21004245200000 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 21004245200000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26429201860320).

21004245200000 is an abundant number, since it is smaller than the sum of its proper divisors (31854158520640).

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

21004245200000 is an equidigital number, since it uses as much as digits as its factorization.

21004245200000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1642 (or 1610 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

Adding to 21004245200000 its reverse (254240012), we get a palindrome (21004499440012).

The spelling of 21004245200000 in words is "twenty-one trillion, four billion, two hundred forty-five million, two hundred thousand".