20210121100 has 36 divisors (see below), whose sum is σ = 47229501424. Its totient is φ = 7462198080.

The previous prime is 20210121089. The next prime is 20210121209. The reversal of 20210121100 is 112101202.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7771824 + ... + 7774423.

Almost surely, 2^20210121100 is an apocalyptic number.

20210121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20210121100 is an abundant number, since it is smaller than the sum of its proper divisors (27019380324).

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

20210121100 is a wasteful number, since it uses less digits than its factorization.

20210121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15546274 (or 15546267 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20210121100 its reverse (112101202), we get a palindrome (20322222302).

The spelling of 20210121100 in words is "twenty billion, two hundred ten million, one hundred twenty-one thousand, one hundred".