20121012090 has 64 divisors (see below), whose sum is σ = 53675481600. Its totient is φ = 5363658432.

The previous prime is 20121012089. The next prime is 20121012091. The reversal of 20121012090 is 9021012102.

It is an interprime number because it is at equal distance from previous prime (20121012089) and next prime (20121012091).

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

It is not an unprimeable number, because it can be changed into a prime (20121012091) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 830184 + ... + 854076.

It is an arithmetic number, because the mean of its divisors is an integer number (838679400).

Almost surely, 2^20121012090 is an apocalyptic number.

20121012090 is an abundant number, since it is smaller than the sum of its proper divisors (33554469510).

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

20121012090 is a wasteful number, since it uses less digits than its factorization.

20121012090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27028 (or 27022 counting only the distinct ones).

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

Adding to 20121012090 its reverse (9021012102), we get a palindrome (29142024192).

The spelling of 20121012090 in words is "twenty billion, one hundred twenty-one million, twelve thousand, ninety".