20077997 has 2 divisors, whose sum is σ = 20077998. Its totient is φ = 20077996.

The previous prime is 20077979. The next prime is 20077999. The reversal of 20077997 is 79977002.

It is a happy number.

Together with previous prime (20077979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18887716 + 1190281 = 4346^2 + 1091^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20077997 is a prime.

Together with 20077999, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20077999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10038998 + 10038999.

It is an arithmetic number, because the mean of its divisors is an integer number (10038999).

Almost surely, 2^20077997 is an apocalyptic number.

It is an amenable number.

20077997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20077997 is an equidigital number, since it uses as much as digits as its factorization.

20077997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 55566, while the sum is 41.

The square root of 20077997 is about 4480.8477992451. The cubic root of 20077997 is about 271.7941646675.

The spelling of 20077997 in words is "twenty million, seventy-seven thousand, nine hundred ninety-seven".