420751 has 4 divisors (see below), whose sum is σ = 424192. Its totient is φ = 417312.

The previous prime is 420743. The next prime is 420757. The reversal of 420751 is 157024.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 420751 - 2³ = 420743 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 (420757) 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, 1530 + ... + 1783.

It is an arithmetic number, because the mean of its divisors is an integer number (106048).

2⁴²⁰⁷⁵¹ is an apocalyptic number.

420751 is the 375-th hex number.

420751 is a deficient number, since it is larger than the sum of its proper divisors (3441).

420751 is a wasteful number, since it uses less digits than its factorization.

420751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3440.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 420751 is about 648.6532201415. The cubic root of 420751 is about 74.9333333509.

Adding to 420751 its reverse (157024), we get a palindrome (577775).

The spelling of 420751 in words is "four hundred twenty thousand, seven hundred fifty-one".