20293661 has 4 divisors (see below), whose sum is σ = 20502972. Its totient is φ = 20084352.

The previous prime is 20293657. The next prime is 20293687. The reversal of 20293661 is 16639202.

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 3728761 + 16564900 = 1931^2 + 4070^2 .

It is a cyclic number.

It is not a de Polignac number, because 20293661 - 2² = 20293657 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 (20293961) 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, 104510 + ... + 104703.

It is an arithmetic number, because the mean of its divisors is an integer number (5125743).

Almost surely, 2^20293661 is an apocalyptic number.

It is an amenable number.

20293661 is a deficient number, since it is larger than the sum of its proper divisors (209311).

20293661 is an equidigital number, since it uses as much as digits as its factorization.

20293661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209310.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 20293661 is about 4504.8486101089. The cubic root of 20293661 is about 272.7638428772.

The spelling of 20293661 in words is "twenty million, two hundred ninety-three thousand, six hundred sixty-one".