20111001012 has 36 divisors (see below), whose sum is σ = 50841275940. Its totient is φ = 6702989952.

The previous prime is 20111000951. The next prime is 20111001013. The reversal of 20111001012 is 21010011102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10888087716 + 9222913296 = 104346^2 + 96036^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 20111000985 and 20111001003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111001013) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 439318 + ... + 482930.

It is an arithmetic number, because the mean of its divisors is an integer number (1412257665).

Almost surely, 2^20111001012 is an apocalyptic number.

It is an amenable number.

20111001012 is an abundant number, since it is smaller than the sum of its proper divisors (30730274928).

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

20111001012 is a wasteful number, since it uses less digits than its factorization.

20111001012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56432 (or 56427 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20111001012 its reverse (21010011102), we get a palindrome (41121012114).

The spelling of 20111001012 in words is "twenty billion, one hundred eleven million, one thousand, twelve".