221061185287 has 4 divisors (see below), whose sum is σ = 228192191296. Its totient is φ = 213930179280.

The previous prime is 221061185251. The next prime is 221061185339. The reversal of 221061185287 is 782581160122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221061185287 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 (221061185207) 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, 3565502958 + ... + 3565503019.

It is an arithmetic number, because the mean of its divisors is an integer number (57048047824).

Almost surely, 2^221061185287 is an apocalyptic number.

221061185287 is a deficient number, since it is larger than the sum of its proper divisors (7131006009).

221061185287 is an equidigital number, since it uses as much as digits as its factorization.

221061185287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7131006008.

The product of its (nonzero) digits is 107520, while the sum is 43.

The spelling of 221061185287 in words is "two hundred twenty-one billion, sixty-one million, one hundred eighty-five thousand, two hundred eighty-seven".