20680451 has 16 divisors (see below), whose sum is σ = 23522400. Its totient is φ = 18009600.

The previous prime is 20680433. The next prime is 20680453. The reversal of 20680451 is 15408602.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20680451 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20680451.

It is not an unprimeable number, because it can be changed into a prime (20680453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76745 + ... + 77013.

It is an arithmetic number, because the mean of its divisors is an integer number (1470150).

Almost surely, 2^20680451 is an apocalyptic number.

20680451 is a deficient number, since it is larger than the sum of its proper divisors (2841949).

20680451 is a wasteful number, since it uses less digits than its factorization.

20680451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20680451 is about 4547.5763874838. The cubic root of 20680451 is about 274.4858757855.

The spelling of 20680451 in words is "twenty million, six hundred eighty thousand, four hundred fifty-one".