213940644 has 24 divisors (see below), whose sum is σ = 503129088. Its totient is φ = 70751520.

The previous prime is 213940619. The next prime is 213940669. The reversal of 213940644 is 446049312.

It is an interprime number because it is at equal distance from previous prime (213940619) and next prime (213940669).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68667 + ... + 71714.

It is an arithmetic number, because the mean of its divisors is an integer number (20963712).

Almost surely, 2^213940644 is an apocalyptic number.

It is an amenable number.

213940644 is an abundant number, since it is smaller than the sum of its proper divisors (289188444).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

213940644 is a wasteful number, since it uses less digits than its factorization.

213940644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140515 (or 140513 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 213940644 is about 14626.7099513185. The cubic root of 213940644 is about 598.0870967051.

Adding to 213940644 its reverse (446049312), we get a palindrome (659989956).

The spelling of 213940644 in words is "two hundred thirteen million, nine hundred forty thousand, six hundred forty-four".