1217631243 has 32 divisors (see below), whose sum is σ = 1687795200. Its totient is φ = 780307200.

The previous prime is 1217631229. The next prime is 1217631251. The reversal of 1217631243 is 3421367121.

It is a happy number.

It is not a de Polignac number, because 1217631243 - 2¹⁶ = 1217565707 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1217631243.

It is not an unprimeable number, because it can be changed into a prime (1217631223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3915058 + ... + 3915368.

It is an arithmetic number, because the mean of its divisors is an integer number (52743600).

Almost surely, 2^1217631243 is an apocalyptic number.

1217631243 is a deficient number, since it is larger than the sum of its proper divisors (470163957).

1217631243 is a wasteful number, since it uses less digits than its factorization.

1217631243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723.

The product of its digits is 6048, while the sum is 30.

The square root of 1217631243 is about 34894.5732600357. The cubic root of 1217631243 is about 1067.8377281897.

Adding to 1217631243 its reverse (3421367121), we get a palindrome (4638998364).

The spelling of 1217631243 in words is "one billion, two hundred seventeen million, six hundred thirty-one thousand, two hundred forty-three".