421569 has 12 divisors (see below), whose sum is σ = 628992. Its totient is φ = 271800.

The previous prime is 421559. The next prime is 421607. The reversal of 421569 is 965124.

It is not a de Polignac number, because 421569 - 2⁸ = 421313 is a prime.

It is a super-2 number, since 2×421569² = 355440843522, which contains 22 as substring.

421569 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (421559) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 477 + ... + 1034.

It is an arithmetic number, because the mean of its divisors is an integer number (52416).

2⁴²¹⁵⁶⁹ is an apocalyptic number.

It is an amenable number.

421569 is a deficient number, since it is larger than the sum of its proper divisors (207423).

421569 is a wasteful number, since it uses less digits than its factorization.

421569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548 (or 1545 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 421569 is about 649.2834511983. The cubic root of 421569 is about 74.9818622807.

It can be divided in two parts, 421 and 569, that added together give a triangular number (990 = T₄₄).

The spelling of 421569 in words is "four hundred twenty-one thousand, five hundred sixty-nine".