20111221012 has 24 divisors (see below), whose sum is σ = 35446410272. Its totient is φ = 9983800800.

The previous prime is 20111221003. The next prime is 20111221021. The reversal of 20111221012 is 21012211102.

It is an interprime number because it is at equal distance from previous prime (20111221003) and next prime (20111221021).

It is a super-2 number, since 2×20111221012² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20111220983 and 20111221001.

It is a congruent number.

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, 650587 + ... + 680797.

Almost surely, 2^20111221012 is an apocalyptic number.

It is an amenable number.

20111221012 is a deficient number, since it is larger than the sum of its proper divisors (15335189260).

20111221012 is a wasteful number, since it uses less digits than its factorization.

20111221012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31399 (or 31397 counting only the distinct ones).

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

Adding to 20111221012 its reverse (21012211102), we get a palindrome (41123432114).

The spelling of 20111221012 in words is "twenty billion, one hundred eleven million, two hundred twenty-one thousand, twelve".