421439841 has 15 divisors (see below), whose sum is σ = 629834403. Its totient is φ = 280836720.

The previous prime is 421439827. The next prime is 421439867. The reversal of 421439841 is 148934124.

It is a happy number.

The square root of 421439841 is 20529.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 253478241 + 167961600 = 15921^2 + 12960^2 .

It is not a de Polignac number, because 421439841 - 2⁷ = 421439713 is a prime.

It is a super-2 number, since 2×421439841² = 355223079164210562, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 421439796 and 421439805.

It is not an unprimeable number, because it can be changed into a prime (421439881) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 183621 + ... + 185901.

Almost surely, 2^421439841 is an apocalyptic number.

421439841 is the 20529-th square number.

421439841 is the 10265-th centered octagonal number.

It is an amenable number.

421439841 is a deficient number, since it is larger than the sum of its proper divisors (208394562).

421439841 is an frugal number, since it uses more digits than its factorization.

421439841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4574 (or 2284 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The cubic root of 421439841 is about 749.7420392852.

Multiplying 421439841 by its sum of digits (36), we get a square (15171834276 = 123174²).

It can be divided in two parts, 42143 and 9841, that added together give a square (51984 = 228²).

The spelling of 421439841 in words is "four hundred twenty-one million, four hundred thirty-nine thousand, eight hundred forty-one".