20001220100988 has 96 divisors (see below), whose sum is σ = 53901827578368. Its totient is φ = 5654150880000.

The previous prime is 20001220100959. The next prime is 20001220100993. The reversal of 20001220100988 is 88900102210002.

It is a super-2 number, since 2×20001220100988² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11497906 + ... + 13122662.

It is an arithmetic number, because the mean of its divisors is an integer number (561477370608).

Almost surely, 2^{20001220100988} is an apocalyptic number.

20001220100988 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20001220100988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26950913789184).

20001220100988 is an abundant number, since it is smaller than the sum of its proper divisors (33900607477380).

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

20001220100988 is a wasteful number, since it uses less digits than its factorization.

20001220100988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1626323 (or 1626321 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 33.

The spelling of 20001220100988 in words is "twenty trillion, one billion, two hundred twenty million, one hundred thousand, nine hundred eighty-eight".