213121003 has 4 divisors (see below), whose sum is σ = 217142208. Its totient is φ = 209099800.

The previous prime is 213120979. The next prime is 213121019. The reversal of 213121003 is 300121312.

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 213121003 - 2⁹ = 213120491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213121093) 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, 2010523 + ... + 2010628.

It is an arithmetic number, because the mean of its divisors is an integer number (54285552).

Almost surely, 2^213121003 is an apocalyptic number.

213121003 is a deficient number, since it is larger than the sum of its proper divisors (4021205).

213121003 is an equidigital number, since it uses as much as digits as its factorization.

213121003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4021204.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 213121003 is about 14598.6644252137. The cubic root of 213121003 is about 597.3223299521.

Adding to 213121003 its reverse (300121312), we get a palindrome (513242315).

The spelling of 213121003 in words is "two hundred thirteen million, one hundred twenty-one thousand, three".