20001122111961 has 20 divisors (see below), whose sum is σ = 29901185188644. Its totient is φ = 13323832236000.

The previous prime is 20001122111879. The next prime is 20001122111963. The reversal of 20001122111961 is 16911122110002.

It can be written as a sum of positive squares in 2 ways, for example, as 344809712025 + 19656312399936 = 587205^2 + 4433544^2 .

It is not a de Polignac number, because 20001122111961 - 2⁷ = 20001122111833 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20001122111963) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 94793710 + ... + 95004471.

Almost surely, 2^{20001122111961} is an apocalyptic number.

It is an amenable number.

20001122111961 is a deficient number, since it is larger than the sum of its proper divisors (9900063076683).

20001122111961 is a wasteful number, since it uses less digits than its factorization.

20001122111961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189799494 (or 189799485 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 27.

Adding to 20001122111961 its reverse (16911122110002), we get a palindrome (36912244221963).

The spelling of 20001122111961 in words is "twenty trillion, one billion, one hundred twenty-two million, one hundred eleven thousand, nine hundred sixty-one".