21201102121000 has 32 divisors (see below), whose sum is σ = 49610578965480. Its totient is φ = 8480440848000.

The previous prime is 21201102120983. The next prime is 21201102121013. The reversal of 21201102121000 is 12120110212.

It can be written as a sum of positive squares in 4 ways, for example, as 5492451585604 + 15708650535396 = 2343598^2 + 3963414^2 .

It is a super-2 number, since 2×21201102121000² (a number of 27 digits) contains 22 as substring.

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, 10600550061 + ... + 10600552060.

Almost surely, 2^{21201102121000} is an apocalyptic number.

21201102121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201102121000 is an abundant number, since it is smaller than the sum of its proper divisors (28409476844480).

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

21201102121000 is a wasteful number, since it uses less digits than its factorization.

21201102121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21201102142 (or 21201102128 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21201102121000 its reverse (12120110212), we get a palindrome (21213222231212).

The spelling of 21201102121000 in words is "twenty-one trillion, two hundred one billion, one hundred two million, one hundred twenty-one thousand".