420340637 has 2 divisors, whose sum is σ = 420340638. Its totient is φ = 420340636.

The previous prime is 420340601. The next prime is 420340639. The reversal of 420340637 is 736043024.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 413756281 + 6584356 = 20341^2 + 2566^2 .

It is a cyclic number.

It is not a de Polignac number, because 420340637 - 2²⁴ = 403563421 is a prime.

It is a super-2 number, since 2×420340637² = 353372502227131538, which contains 22 as substring.

Together with 420340639, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_22361591 and since 420340637 and 22361591 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420340639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210170318 + 210170319.

It is an arithmetic number, because the mean of its divisors is an integer number (210170319).

Almost surely, 2^420340637 is an apocalyptic number.

It is an amenable number.

420340637 is a deficient number, since it is larger than the sum of its proper divisors (1).

420340637 is an equidigital number, since it uses as much as digits as its factorization.

420340637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 29.

The square root of 420340637 is about 20502.2105393540. The cubic root of 420340637 is about 749.0896432998.

The spelling of 420340637 in words is "four hundred twenty million, three hundred forty thousand, six hundred thirty-seven".