20993719 has 2 divisors, whose sum is σ = 20993720. Its totient is φ = 20993718.

The previous prime is 20993717. The next prime is 20993741. The reversal of 20993719 is 91739902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20993719 - 2¹ = 20993717 is a prime.

It is a super-2 number, since 2×20993719² = 881472474901922, which contains 22 as substring.

Together with 20993717, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20993717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10496859 + 10496860.

It is an arithmetic number, because the mean of its divisors is an integer number (10496860).

Almost surely, 2^20993719 is an apocalyptic number.

20993719 is a deficient number, since it is larger than the sum of its proper divisors (1).

20993719 is an equidigital number, since it uses as much as digits as its factorization.

20993719 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 20993719 is about 4581.8903304204. The cubic root of 20993719 is about 275.8649088592.

It can be divided in two parts, 20993 and 719, that added together give a palindrome (21712).

The spelling of 20993719 in words is "twenty million, nine hundred ninety-three thousand, seven hundred nineteen".