20601556100 has 36 divisors (see below), whose sum is σ = 44712531444. Its totient is φ = 8239303680.

The previous prime is 20601556099. The next prime is 20601556117. The reversal of 20601556100 is 165510602.

It can be written as a sum of positive squares in 6 ways, for example, as 6082752064 + 14518804036 = 77992^2 + 120494^2 .

It is a super-2 number, since 2×20601556100² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20601556100.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 825404 + ... + 849996.

Almost surely, 2^20601556100 is an apocalyptic number.

20601556100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20601556100 is an abundant number, since it is smaller than the sum of its proper divisors (24110975344).

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

20601556100 is a wasteful number, since it uses less digits than its factorization.

20601556100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32984 (or 32977 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 26.

The spelling of 20601556100 in words is "twenty billion, six hundred one million, five hundred fifty-six thousand, one hundred".