221331220156 has 12 divisors (see below), whose sum is σ = 387566256168. Its totient is φ = 110598004112.

The previous prime is 221331220133. The next prime is 221331220157. The reversal of 221331220156 is 651022133122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221331220157) 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, 16894126 + ... + 16907221.

It is an arithmetic number, because the mean of its divisors is an integer number (32297188014).

Almost surely, 2^221331220156 is an apocalyptic number.

It is an amenable number.

221331220156 is a deficient number, since it is larger than the sum of its proper divisors (166235036012).

221331220156 is a wasteful number, since it uses less digits than its factorization.

221331220156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33802988 (or 33802986 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

Adding to 221331220156 its reverse (651022133122), we get a palindrome (872353353278).

The spelling of 221331220156 in words is "two hundred twenty-one billion, three hundred thirty-one million, two hundred twenty thousand, one hundred fifty-six".