421540155 has 12 divisors (see below), whose sum is σ = 730669680. Its totient is φ = 224821392.

The previous prime is 421540153. The next prime is 421540187. The reversal of 421540155 is 551045124.

It is not a de Polignac number, because 421540155 - 2¹ = 421540153 is a prime.

It is a super-2 number, since 2×421540155² = 355392204554848050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (421540153) 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, 4683735 + ... + 4683824.

It is an arithmetic number, because the mean of its divisors is an integer number (60889140).

Almost surely, 2^421540155 is an apocalyptic number.

421540155 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

421540155 is a deficient number, since it is larger than the sum of its proper divisors (309129525).

421540155 is a wasteful number, since it uses less digits than its factorization.

421540155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9367570 (or 9367567 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

The square root of 421540155 is about 20531.4430812839. The cubic root of 421540155 is about 749.8015208126.

Adding to 421540155 its reverse (551045124), we get a palindrome (972585279).

The spelling of 421540155 in words is "four hundred twenty-one million, five hundred forty thousand, one hundred fifty-five".