213531503 has 4 divisors (see below), whose sum is σ = 220419648. Its totient is φ = 206643360.

The previous prime is 213531499. The next prime is 213531523. The reversal of 213531503 is 305135312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 213531503 - 2² = 213531499 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213531523) 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, 3444026 + ... + 3444087.

It is an arithmetic number, because the mean of its divisors is an integer number (55104912).

Almost surely, 2^213531503 is an apocalyptic number.

213531503 is a deficient number, since it is larger than the sum of its proper divisors (6888145).

213531503 is an equidigital number, since it uses as much as digits as its factorization.

213531503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6888144.

The product of its (nonzero) digits is 1350, while the sum is 23.

The square root of 213531503 is about 14612.7171669064. The cubic root of 213531503 is about 597.7055919664.

Adding to 213531503 its reverse (305135312), we get a palindrome (518666815).

The spelling of 213531503 in words is "two hundred thirteen million, five hundred thirty-one thousand, five hundred three".