21077100 has 108 divisors (see below), whose sum is σ = 72104760. Its totient is φ = 5107200.

The previous prime is 21077081. The next prime is 21077123. The reversal of 21077100 is 177012.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 8836 + ... + 10964.

Almost surely, 2^21077100 is an apocalyptic number.

21077100 is a gapful number since it is divisible by the number (20) 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 21077100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36052380).

21077100 is an abundant number, since it is smaller than the sum of its proper divisors (51027660).

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

21077100 is a wasteful number, since it uses less digits than its factorization.

21077100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2160 (or 2150 counting only the distinct ones).

The product of its (nonzero) digits is 98, while the sum is 18.

The square root of 21077100 is about 4590.9802874767. The cubic root of 21077100 is about 276.2296450404.

The spelling of 21077100 in words is "twenty-one million, seventy-seven thousand, one hundred".