20893817 has 4 divisors (see below), whose sum is σ = 23878656. Its totient is φ = 17908980.

The previous prime is 20893811. The next prime is 20893849. The reversal of 20893817 is 71839802.

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, and also an emirpimes, since its reverse is a distinct semiprime: 71839802 = 2 ⋅35919901.

It is a cyclic number.

It is not a de Polignac number, because 20893817 - 2⁶ = 20893753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20893811) 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, 1492409 + ... + 1492422.

It is an arithmetic number, because the mean of its divisors is an integer number (5969664).

Almost surely, 2^20893817 is an apocalyptic number.

It is an amenable number.

20893817 is a deficient number, since it is larger than the sum of its proper divisors (2984839).

20893817 is an equidigital number, since it uses as much as digits as its factorization.

20893817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2984838.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 20893817 is about 4570.9754976372. The cubic root of 20893817 is about 275.4266303526.

The spelling of 20893817 in words is "twenty million, eight hundred ninety-three thousand, eight hundred seventeen".