1223781647 has 4 divisors (see below), whose sum is σ = 1335034536. Its totient is φ = 1112528760.

The previous prime is 1223781617. The next prime is 1223781649. The reversal of 1223781647 is 7461873221.

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 1223781647 - 2¹² = 1223777551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223781649) 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, 55626428 + ... + 55626449.

It is an arithmetic number, because the mean of its divisors is an integer number (333758634).

Almost surely, 2^1223781647 is an apocalyptic number.

1223781647 is a deficient number, since it is larger than the sum of its proper divisors (111252889).

1223781647 is a wasteful number, since it uses less digits than its factorization.

1223781647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111252888.

The product of its digits is 112896, while the sum is 41.

The square root of 1223781647 is about 34982.5906273392. The cubic root of 1223781647 is about 1069.6326357001.

The spelling of 1223781647 in words is "one billion, two hundred twenty-three million, seven hundred eighty-one thousand, six hundred forty-seven".