20493965 has 4 divisors (see below), whose sum is σ = 24592764. Its totient is φ = 16395168.

The previous prime is 20493961. The next prime is 20493971. The reversal of 20493965 is 56939402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9853321 + 10640644 = 3139^2 + 3262^2 .

It is a cyclic number.

It is not a de Polignac number, because 20493965 - 2² = 20493961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20493961) 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 3 ways as a sum of consecutive naturals, for example, 2049392 + ... + 2049401.

It is an arithmetic number, because the mean of its divisors is an integer number (6148191).

Almost surely, 2^20493965 is an apocalyptic number.

It is an amenable number.

20493965 is a deficient number, since it is larger than the sum of its proper divisors (4098799).

20493965 is an equidigital number, since it uses as much as digits as its factorization.

20493965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4098798.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 20493965 is about 4527.0260657522. The cubic root of 20493965 is about 273.6583243547.

The spelling of 20493965 in words is "twenty million, four hundred ninety-three thousand, nine hundred sixty-five".