420636350203661 has 2 divisors, whose sum is σ = 420636350203662. Its totient is φ = 420636350203660.

The previous prime is 420636350203649. The next prime is 420636350203733. The reversal of 420636350203661 is 166302053636024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 345153007950436 + 75483342253225 = 18578294^2 + 8688115^2 .

It is a cyclic number.

It is not a de Polignac number, because 420636350203661 - 2²² = 420636346009357 is a prime.

It is a super-2 number, since 2×420636350203661² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420636350203621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210318175101830 + 210318175101831.

It is an arithmetic number, because the mean of its divisors is an integer number (210318175101831).

Almost surely, 2^{420636350203661} is an apocalyptic number.

It is an amenable number.

420636350203661 is a deficient number, since it is larger than the sum of its proper divisors (1).

420636350203661 is an equidigital number, since it uses as much as digits as its factorization.

420636350203661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2799360, while the sum is 47.

The spelling of 420636350203661 in words is "four hundred twenty trillion, six hundred thirty-six billion, three hundred fifty million, two hundred three thousand, six hundred sixty-one".