20739619 has 2 divisors, whose sum is σ = 20739620. Its totient is φ = 20739618.

The previous prime is 20739617. The next prime is 20739661. The reversal of 20739619 is 91693702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20739619 - 2¹ = 20739617 is a prime.

It is a super-2 number, since 2×20739619² = 860263592530322, which contains 22 as substring.

Together with 20739617, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20739617) 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 as a sum of consecutive naturals, namely, 10369809 + 10369810.

It is an arithmetic number, because the mean of its divisors is an integer number (10369810).

Almost surely, 2^20739619 is an apocalyptic number.

20739619 is a deficient number, since it is larger than the sum of its proper divisors (1).

20739619 is an equidigital number, since it uses as much as digits as its factorization.

20739619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 20739619 is about 4554.0771842383. The cubic root of 20739619 is about 274.7474000024.

The spelling of 20739619 in words is "twenty million, seven hundred thirty-nine thousand, six hundred nineteen".