20187697 has 2 divisors, whose sum is σ = 20187698. Its totient is φ = 20187696.

The previous prime is 20187689. The next prime is 20187701. The reversal of 20187697 is 79678102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16638241 + 3549456 = 4079^2 + 1884^2 .

It is a cyclic number.

It is not a de Polignac number, because 20187697 - 2³ = 20187689 is a prime.

It is a super-2 number, since 2×20187697² = 815086220327618, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20187637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10093848 + 10093849.

It is an arithmetic number, because the mean of its divisors is an integer number (10093849).

Almost surely, 2^20187697 is an apocalyptic number.

It is an amenable number.

20187697 is a deficient number, since it is larger than the sum of its proper divisors (1).

20187697 is an equidigital number, since it uses as much as digits as its factorization.

20187697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 20187697 is about 4493.0721115958. The cubic root of 20187697 is about 272.2882657906.

The spelling of 20187697 in words is "twenty million, one hundred eighty-seven thousand, six hundred ninety-seven".