20691072 has 64 divisors (see below), whose sum is σ = 61077600. Its totient is φ = 6895872.

The previous prime is 20691071. The next prime is 20691079. The reversal of 20691072 is 27019602.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20691071) 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 7 ways as a sum of consecutive naturals, for example, 463 + ... + 6449.

Almost surely, 2^20691072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20691072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30538800).

20691072 is an abundant number, since it is smaller than the sum of its proper divisors (40386528).

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

20691072 is an equidigital number, since it uses as much as digits as its factorization.

20691072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6010 (or 5992 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 20691072 is about 4548.7440024693. The cubic root of 20691072 is about 274.5328576034.

The spelling of 20691072 in words is "twenty million, six hundred ninety-one thousand, seventy-two".