1217986772 has 12 divisors (see below), whose sum is σ = 2150340276. Its totient is φ = 603603840.

The previous prime is 1217986751. The next prime is 1217986789. The reversal of 1217986772 is 2776897121.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 471932176 + 746054596 = 21724^2 + 27314^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1217986772.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1346879 + ... + 1347782.

It is an arithmetic number, because the mean of its divisors is an integer number (179195023).

Almost surely, 2^1217986772 is an apocalyptic number.

It is an amenable number.

1217986772 is a deficient number, since it is larger than the sum of its proper divisors (932353504).

1217986772 is a wasteful number, since it uses less digits than its factorization.

1217986772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2694778 (or 2694776 counting only the distinct ones).

The product of its digits is 592704, while the sum is 50.

The square root of 1217986772 is about 34899.6672190438. The cubic root of 1217986772 is about 1067.9416486330.

The spelling of 1217986772 in words is "one billion, two hundred seventeen million, nine hundred eighty-six thousand, seven hundred seventy-two".