20455691 has 8 divisors (see below), whose sum is σ = 21178368. Its totient is φ = 19737000.

The previous prime is 20455681. The next prime is 20455711. The reversal of 20455691 is 19655402.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20455691 - 2⁶ = 20455627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20455601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12596 + ... + 14126.

It is an arithmetic number, because the mean of its divisors is an integer number (2647296).

Almost surely, 2^20455691 is an apocalyptic number.

20455691 is a deficient number, since it is larger than the sum of its proper divisors (722677).

20455691 is a wasteful number, since it uses less digits than its factorization.

20455691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1993.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 20455691 is about 4522.7968117084. The cubic root of 20455691 is about 273.4878591177.

The spelling of 20455691 in words is "twenty million, four hundred fifty-five thousand, six hundred ninety-one".