20639077 has 2 divisors, whose sum is σ = 20639078. Its totient is φ = 20639076.

The previous prime is 20639057. The next prime is 20639093. The reversal of 20639077 is 77093602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17969121 + 2669956 = 4239^2 + 1634^2 .

It is a cyclic number.

It is not a de Polignac number, because 20639077 - 2¹⁵ = 20606309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20639057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10319538 + 10319539.

It is an arithmetic number, because the mean of its divisors is an integer number (10319539).

Almost surely, 2^20639077 is an apocalyptic number.

It is an amenable number.

20639077 is a deficient number, since it is larger than the sum of its proper divisors (1).

20639077 is an equidigital number, since it uses as much as digits as its factorization.

20639077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15876, while the sum is 34.

The square root of 20639077 is about 4543.0250934812. The cubic root of 20639077 is about 274.3027050461.

The spelling of 20639077 in words is "twenty million, six hundred thirty-nine thousand, seventy-seven".