420990 has 16 divisors (see below), whose sum is σ = 1010448. Its totient is φ = 112256.

The previous prime is 420977. The next prime is 420997. The reversal of 420990 is 99024.

It is a self number, because there is not a number n which added to its sum of digits gives 420990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6987 + ... + 7046.

It is an arithmetic number, because the mean of its divisors is an integer number (63153).

2⁴²⁰⁹⁹⁰ is an apocalyptic number.

420990 is an abundant number, since it is smaller than the sum of its proper divisors (589458).

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

420990 is a wasteful number, since it uses less digits than its factorization.

420990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14043.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 420990 is about 648.8374218554. The cubic root of 420990 is about 74.9475188405.

The spelling of 420990 in words is "four hundred twenty thousand, nine hundred ninety".