213979145 has 4 divisors (see below), whose sum is σ = 256774980. Its totient is φ = 171183312.

The previous prime is 213979141. The next prime is 213979147. The reversal of 213979145 is 541979312.

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 61011721 + 152967424 = 7811^2 + 12368^2 .

It is a cyclic number.

It is not a de Polignac number, because 213979145 - 2² = 213979141 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (213979141) 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, 21397910 + ... + 21397919.

It is an arithmetic number, because the mean of its divisors is an integer number (64193745).

Almost surely, 2^213979145 is an apocalyptic number.

It is an amenable number.

213979145 is a deficient number, since it is larger than the sum of its proper divisors (42795835).

213979145 is an equidigital number, since it uses as much as digits as its factorization.

213979145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42795834.

The product of its digits is 68040, while the sum is 41.

The square root of 213979145 is about 14628.0260117351. The cubic root of 213979145 is about 598.1229720296.

The spelling of 213979145 in words is "two hundred thirteen million, nine hundred seventy-nine thousand, one hundred forty-five".