213545649 has 4 divisors (see below), whose sum is σ = 284727536. Its totient is φ = 142363764.

The previous prime is 213545609. The next prime is 213545663. The reversal of 213545649 is 946545312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 213545649 - 2²⁰ = 212497073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213545609) 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, 35590939 + ... + 35590944.

It is an arithmetic number, because the mean of its divisors is an integer number (71181884).

Almost surely, 2^213545649 is an apocalyptic number.

It is an amenable number.

213545649 is a deficient number, since it is larger than the sum of its proper divisors (71181887).

213545649 is an equidigital number, since it uses as much as digits as its factorization.

213545649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71181886.

The product of its digits is 129600, while the sum is 39.

The square root of 213545649 is about 14613.2011893356. The cubic root of 213545649 is about 597.7187905756.

The spelling of 213545649 in words is "two hundred thirteen million, five hundred forty-five thousand, six hundred forty-nine".