420745261 has 4 divisors (see below), whose sum is σ = 420788800. Its totient is φ = 420701724.

The previous prime is 420745249. The next prime is 420745301. The reversal of 420745261 is 162547024.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 420745261 - 2⁷ = 420745133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420745201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51 + ... + 29008.

It is an arithmetic number, because the mean of its divisors is an integer number (105197200).

Almost surely, 2^420745261 is an apocalyptic number.

It is an amenable number.

420745261 is a deficient number, since it is larger than the sum of its proper divisors (43539).

420745261 is a wasteful number, since it uses less digits than its factorization.

420745261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43538.

The product of its (nonzero) digits is 13440, while the sum is 31.

The square root of 420745261 is about 20512.0759797735. The cubic root of 420745261 is about 749.3299265508.

The spelling of 420745261 in words is "four hundred twenty million, seven hundred forty-five thousand, two hundred sixty-one".