420342561 has 32 divisors (see below), whose sum is σ = 661910400. Its totient is φ = 262725120.

The previous prime is 420342557. The next prime is 420342563. The reversal of 420342561 is 165243024.

It is not a de Polignac number, because 420342561 - 2² = 420342557 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (420342563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 127350 + ... + 130608.

It is an arithmetic number, because the mean of its divisors is an integer number (20684700).

Almost surely, 2^420342561 is an apocalyptic number.

It is an amenable number.

420342561 is a deficient number, since it is larger than the sum of its proper divisors (241567839).

420342561 is a wasteful number, since it uses less digits than its factorization.

420342561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3566 (or 3560 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 420342561 is about 20502.2574610700. The cubic root of 420342561 is about 749.0907862191.

Adding to 420342561 its reverse (165243024), we get a palindrome (585585585).

It can be divided in two parts, 420342 and 561, that added together give a triangular number (420903 = T₉₁₇).

The spelling of 420342561 in words is "four hundred twenty million, three hundred forty-two thousand, five hundred sixty-one".