421690 has 8 divisors (see below), whose sum is σ = 759060. Its totient is φ = 168672.

The previous prime is 421661. The next prime is 421691. The reversal of 421690 is 96124.

It can be written as a sum of positive squares in 2 ways, for example, as 393129 + 28561 = 627^2 + 169^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×421690² = 355644912200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (421691) 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, 21075 + ... + 21094.

2⁴²¹⁶⁹⁰ is an apocalyptic number.

421690 is a deficient number, since it is larger than the sum of its proper divisors (337370).

421690 is a wasteful number, since it uses less digits than its factorization.

421690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42176.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 421690 is about 649.3766241558. The cubic root of 421690 is about 74.9890354342.

It can be divided in two parts, 421 and 690, that added together give a palindrome (1111).

The spelling of 421690 in words is "four hundred twenty-one thousand, six hundred ninety".