345515021 has 4 divisors (see below), whose sum is σ = 365839452. Its totient is φ = 325190592.

The previous prime is 345515011. The next prime is 345515069. The reversal of 345515021 is 120515543.

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 264712900 + 80802121 = 16270^2 + 8989^2 .

It is a cyclic number.

It is not a de Polignac number, because 345515021 - 2¹⁸ = 345252877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (345515011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10162190 + ... + 10162223.

It is an arithmetic number, because the mean of its divisors is an integer number (91459863).

Almost surely, 2^345515021 is an apocalyptic number.

It is an amenable number.

345515021 is a deficient number, since it is larger than the sum of its proper divisors (20324431).

345515021 is a wasteful number, since it uses less digits than its factorization.

345515021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20324430.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 345515021 is about 18588.0343500866. The cubic root of 345515021 is about 701.7067339136.

The spelling of 345515021 in words is "three hundred forty-five million, five hundred fifteen thousand, twenty-one".