221770781006 has 4 divisors (see below), whose sum is σ = 332656171512. Its totient is φ = 110885390502.

The previous prime is 221770780981. The next prime is 221770781021. The reversal of 221770781006 is 600187077122.

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

It is a super-2 number, since 2×221770781006² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55442695250 + ... + 55442695253.

It is an arithmetic number, because the mean of its divisors is an integer number (83164042878).

Almost surely, 2^221770781006 is an apocalyptic number.

221770781006 is a deficient number, since it is larger than the sum of its proper divisors (110885390506).

221770781006 is a wasteful number, since it uses less digits than its factorization.

221770781006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110885390505.

The product of its (nonzero) digits is 65856, while the sum is 41.

The spelling of 221770781006 in words is "two hundred twenty-one billion, seven hundred seventy million, seven hundred eighty-one thousand, six".