420690 has 32 divisors (see below), whose sum is σ = 1039680. Its totient is φ = 108864.

The previous prime is 420683. The next prime is 420691. The reversal of 420690 is 96024.

It is a super-2 number, since 2×420690² = 353960152200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420691) by changing a digit.

420690 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 921 + ... + 1299.

It is an arithmetic number, because the mean of its divisors is an integer number (32490).

2⁴²⁰⁶⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 420690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (519840).

420690 is an abundant number, since it is smaller than the sum of its proper divisors (618990).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

420690 is a wasteful number, since it uses less digits than its factorization.

420690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 426.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 420690 is about 648.6061979352. The cubic root of 420690 is about 74.9297119262.

The spelling of 420690 in words is "four hundred twenty thousand, six hundred ninety".