20845493 has 4 divisors (see below), whose sum is σ = 21109440. Its totient is φ = 20581548.

The previous prime is 20845481. The next prime is 20845499. The reversal of 20845493 is 39454802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20845493 - 2¹⁰ = 20844469 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20845499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131855 + ... + 132012.

It is an arithmetic number, because the mean of its divisors is an integer number (5277360).

Almost surely, 2^20845493 is an apocalyptic number.

It is an amenable number.

20845493 is a deficient number, since it is larger than the sum of its proper divisors (263947).

20845493 is an equidigital number, since it uses as much as digits as its factorization.

20845493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263946.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 20845493 is about 4565.6864763144. The cubic root of 20845493 is about 275.2141274423.

The spelling of 20845493 in words is "twenty million, eight hundred forty-five thousand, four hundred ninety-three".