20739679 has 2 divisors, whose sum is σ = 20739680. Its totient is φ = 20739678.

The previous prime is 20739671. The next prime is 20739689. The reversal of 20739679 is 97693702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20739679 - 2³ = 20739671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20739671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10369839 + 10369840.

It is an arithmetic number, because the mean of its divisors is an integer number (10369840).

Almost surely, 2^20739679 is an apocalyptic number.

20739679 is a deficient number, since it is larger than the sum of its proper divisors (1).

20739679 is an equidigital number, since it uses as much as digits as its factorization.

20739679 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 142884, while the sum is 43.

The square root of 20739679 is about 4554.0837717372. The cubic root of 20739679 is about 274.7476649515.

The spelling of 20739679 in words is "twenty million, seven hundred thirty-nine thousand, six hundred seventy-nine".