213571993 has 8 divisors (see below), whose sum is σ = 218995560. Its totient is φ = 208158720.

The previous prime is 213571991. The next prime is 213571999. The reversal of 213571993 is 399175312.

It can be written as a sum of positive squares in 4 ways, for example, as 43191184 + 170380809 = 6572^2 + 13053^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 213571993 - 2¹ = 213571991 is a prime.

It is a super-2 number, since 2×213571993² = 91225992387984098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213571991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55921 + ... + 59617.

It is an arithmetic number, because the mean of its divisors is an integer number (27374445).

Almost surely, 2^213571993 is an apocalyptic number.

It is an amenable number.

213571993 is a deficient number, since it is larger than the sum of its proper divisors (5423567).

213571993 is a wasteful number, since it uses less digits than its factorization.

213571993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5147.

The product of its digits is 51030, while the sum is 40.

The square root of 213571993 is about 14614.1025383018. The cubic root of 213571993 is about 597.7433687028.

The spelling of 213571993 in words is "two hundred thirteen million, five hundred seventy-one thousand, nine hundred ninety-three".