213321864761 has 4 divisors (see below), whose sum is σ = 213807792000. Its totient is φ = 212835937524.

The previous prime is 213321864653. The next prime is 213321864781. The reversal of 213321864761 is 167468123312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213321864761 is a prime.

It is a super-2 number, since 2×213321864761² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213321864781) 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, 242962961 + ... + 242963838.

It is an arithmetic number, because the mean of its divisors is an integer number (53451948000).

Almost surely, 2^213321864761 is an apocalyptic number.

It is an amenable number.

213321864761 is a deficient number, since it is larger than the sum of its proper divisors (485927239).

213321864761 is an equidigital number, since it uses as much as digits as its factorization.

213321864761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485927238.

The product of its digits is 290304, while the sum is 44.

The spelling of 213321864761 in words is "two hundred thirteen billion, three hundred twenty-one million, eight hundred sixty-four thousand, seven hundred sixty-one".