20210121090 has 48 divisors (see below), whose sum is σ = 54241364736. Its totient is φ = 5215514400.

The previous prime is 20210121089. The next prime is 20210121209. The reversal of 20210121090 is 9012101202.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3619096 + ... + 3624675.

It is an arithmetic number, because the mean of its divisors is an integer number (1130028432).

Almost surely, 2^20210121090 is an apocalyptic number.

20210121090 is an abundant number, since it is smaller than the sum of its proper divisors (34031243646).

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

20210121090 is a wasteful number, since it uses less digits than its factorization.

20210121090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7243815 (or 7243812 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 20210121090 its reverse (9012101202), we get a palindrome (29222222292).

The spelling of 20210121090 in words is "twenty billion, two hundred ten million, one hundred twenty-one thousand, ninety".