21096780 has 48 divisors (see below), whose sum is σ = 59270400. Its totient is φ = 5606848.

The previous prime is 21096763. The next prime is 21096787. The reversal of 21096780 is 8769012.

It is not an unprimeable number, because it can be changed into a prime (21096787) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 34921 + ... + 35519.

It is an arithmetic number, because the mean of its divisors is an integer number (1234800).

Almost surely, 2^21096780 is an apocalyptic number.

21096780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21096780 is an abundant number, since it is smaller than the sum of its proper divisors (38173620).

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

21096780 is a wasteful number, since it uses less digits than its factorization.

21096780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1198 (or 1196 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 21096780 is about 4593.1231204922. The cubic root of 21096780 is about 276.3155915311.

The spelling of 21096780 in words is "twenty-one million, ninety-six thousand, seven hundred eighty".