221691007351 has 4 divisors (see below), whose sum is σ = 241844735304. Its totient is φ = 201537279400.

The previous prime is 221691007333. The next prime is 221691007387. The reversal of 221691007351 is 153700196122.

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 221691007351 - 2⁵ = 221691007319 is a prime.

It is a super-3 number, since 3×221691007351³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221691007351.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221691007651) 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, 10076863960 + ... + 10076863981.

It is an arithmetic number, because the mean of its divisors is an integer number (60461183826).

Almost surely, 2^221691007351 is an apocalyptic number.

221691007351 is a deficient number, since it is larger than the sum of its proper divisors (20153727953).

221691007351 is a wasteful number, since it uses less digits than its factorization.

221691007351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20153727952.

The product of its (nonzero) digits is 22680, while the sum is 37.

The spelling of 221691007351 in words is "two hundred twenty-one billion, six hundred ninety-one million, seven thousand, three hundred fifty-one".