421641531 has 40 divisors (see below), whose sum is σ = 682515504. Its totient is φ = 258370560.

The previous prime is 421641457. The next prime is 421641547. The reversal of 421641531 is 135146124.

It is a happy number.

421641531 is a `hidden beast` number, since 4 + 216 + 415 + 31 = 666.

It is not a de Polignac number, because 421641531 - 2⁷ = 421641403 is a prime.

It is a super-2 number, since 2×421641531² = 355563161328047922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 421641495 and 421641504.

It is not an unprimeable number, because it can be changed into a prime (421641131) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 55651 + ... + 62771.

Almost surely, 2^421641531 is an apocalyptic number.

421641531 is a deficient number, since it is larger than the sum of its proper divisors (260873973).

421641531 is a wasteful number, since it uses less digits than its factorization.

421641531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7193 (or 7184 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 421641531 is about 20533.9117315722. The cubic root of 421641531 is about 749.8616224704.

Adding to 421641531 its reverse (135146124), we get a palindrome (556787655).

The spelling of 421641531 in words is "four hundred twenty-one million, six hundred forty-one thousand, five hundred thirty-one".