213721023 has 8 divisors (see below), whose sum is σ = 285400368. Its totient is φ = 142261184.

The previous prime is 213720989. The next prime is 213721103. The reversal of 213721023 is 320127312.

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 213721023 - 2²² = 209526719 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213728023) 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, 52590 + ... + 56507.

It is an arithmetic number, because the mean of its divisors is an integer number (35675046).

Almost surely, 2^213721023 is an apocalyptic number.

213721023 is a deficient number, since it is larger than the sum of its proper divisors (71679345).

213721023 is a wasteful number, since it uses less digits than its factorization.

213721023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109753.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 213721023 is about 14619.2004911349. The cubic root of 213721023 is about 597.8823709828.

Adding to 213721023 its reverse (320127312), we get a palindrome (533848335).

The spelling of 213721023 in words is "two hundred thirteen million, seven hundred twenty-one thousand, twenty-three".