221540644157 has 16 divisors (see below), whose sum is σ = 266554429440. Its totient is φ = 179871092208.

The previous prime is 221540644147. The next prime is 221540644201. The reversal of 221540644157 is 751446045122.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 221540644157 - 2⁴ = 221540644141 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 (221540644147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 807068 + ... + 1046154.

It is an arithmetic number, because the mean of its divisors is an integer number (16659651840).

Almost surely, 2^221540644157 is an apocalyptic number.

It is an amenable number.

221540644157 is a deficient number, since it is larger than the sum of its proper divisors (45013785283).

221540644157 is a wasteful number, since it uses less digits than its factorization.

221540644157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246080.

The product of its (nonzero) digits is 268800, while the sum is 41.

Adding to 221540644157 its reverse (751446045122), we get a palindrome (972986689279).

The spelling of 221540644157 in words is "two hundred twenty-one billion, five hundred forty million, six hundred forty-four thousand, one hundred fifty-seven".