21210200407720 has 32 divisors (see below), whose sum is σ = 47731810312800. Its totient is φ = 8482505159488.

The previous prime is 21210200407717. The next prime is 21210200407783. The reversal of 21210200407720 is 2770400201212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49000690 + ... + 49431649.

It is an arithmetic number, because the mean of its divisors is an integer number (1491619072275).

Almost surely, 2^{21210200407720} is an apocalyptic number.

21210200407720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210200407720 is an abundant number, since it is smaller than the sum of its proper divisors (26521609905080).

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

21210200407720 is a wasteful number, since it uses less digits than its factorization.

21210200407720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98437737 (or 98437733 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

Adding to 21210200407720 its reverse (2770400201212), we get a palindrome (23980600608932).

The spelling of 21210200407720 in words is "twenty-one trillion, two hundred ten billion, two hundred million, four hundred seven thousand, seven hundred twenty".