16621121020 has 24 divisors (see below), whose sum is σ = 39890690784. Its totient is φ = 5698670016.

The previous prime is 16621120991. The next prime is 16621121053. The reversal of 16621121020 is 2012112661.

It is a super-2 number, since 2×16621121020² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16621120982 and 16621121000.

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, 59361007 + ... + 59361286.

It is an arithmetic number, because the mean of its divisors is an integer number (1662112116).

Almost surely, 2^16621121020 is an apocalyptic number.

16621121020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16621121020 is an abundant number, since it is smaller than the sum of its proper divisors (23269569764).

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

16621121020 is a wasteful number, since it uses less digits than its factorization.

16621121020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118722309 (or 118722307 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 16621121020 its reverse (2012112661), we get a palindrome (18633233681).

It can be divided in two parts, 16621 and 121020, that added together give a square (137641 = 371²).

The spelling of 16621121020 in words is "sixteen billion, six hundred twenty-one million, one hundred twenty-one thousand, twenty".