421520345 has 4 divisors (see below), whose sum is σ = 505824420. Its totient is φ = 337216272.

The previous prime is 421520329. The next prime is 421520353. The reversal of 421520345 is 543025124.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 302099161 + 119421184 = 17381^2 + 10928^2 .

It is a cyclic number.

It is not a de Polignac number, because 421520345 - 2⁴ = 421520329 is a prime.

It is a super-3 number, since 3×421520345³ (a number of 27 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42152030 + ... + 42152039.

It is an arithmetic number, because the mean of its divisors is an integer number (126456105).

Almost surely, 2^421520345 is an apocalyptic number.

It is an amenable number.

421520345 is a deficient number, since it is larger than the sum of its proper divisors (84304075).

421520345 is an equidigital number, since it uses as much as digits as its factorization.

421520345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84304074.

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 421520345 is about 20530.9606448408. The cubic root of 421520345 is about 749.7897751536.

Adding to 421520345 its reverse (543025124), we get a palindrome (964545469).

The spelling of 421520345 in words is "four hundred twenty-one million, five hundred twenty thousand, three hundred forty-five".