215145643 has 4 divisors (see below), whose sum is σ = 218356840. Its totient is φ = 211934448.

The previous prime is 215145629. The next prime is 215145653. The reversal of 215145643 is 346541512.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 215145643 - 2⁹ = 215145131 is a prime.

It is a super-3 number, since 3×215145643³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215145653) 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, 1605498 + ... + 1605631.

It is an arithmetic number, because the mean of its divisors is an integer number (54589210).

Almost surely, 2^215145643 is an apocalyptic number.

215145643 is a deficient number, since it is larger than the sum of its proper divisors (3211197).

215145643 is an equidigital number, since it uses as much as digits as its factorization.

215145643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3211196.

The product of its digits is 14400, while the sum is 31.

The square root of 215145643 is about 14667.8438429102. The cubic root of 215145643 is about 599.2078834161.

The spelling of 215145643 in words is "two hundred fifteen million, one hundred forty-five thousand, six hundred forty-three".