1216923247 has 4 divisors (see below), whose sum is σ = 1218037720. Its totient is φ = 1215808776.

The previous prime is 1216923241. The next prime is 1216923251. The reversal of 1216923247 is 7423296121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7423296121 = 25253 ⋅293957.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1216923247 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 (1216923241) 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, 555597 + ... + 557782.

It is an arithmetic number, because the mean of its divisors is an integer number (304509430).

Almost surely, 2^1216923247 is an apocalyptic number.

1216923247 is a deficient number, since it is larger than the sum of its proper divisors (1114473).

1216923247 is a wasteful number, since it uses less digits than its factorization.

1216923247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1114472.

The product of its digits is 36288, while the sum is 37.

The square root of 1216923247 is about 34884.4269983040. The cubic root of 1216923247 is about 1067.6307220530.

The spelling of 1216923247 in words is "one billion, two hundred sixteen million, nine hundred twenty-three thousand, two hundred forty-seven".