1216422784 has 16 divisors (see below), whose sum is σ = 2423342520. Its totient is φ = 608211328.

The previous prime is 1216422773. The next prime is 1216422787. The reversal of 1216422784 is 4872246121.

It is a tau number, because it is divible by the number of its divisors (16).

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216422787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4751524 + ... + 4751779.

Almost surely, 2^1216422784 is an apocalyptic number.

It is an amenable number.

1216422784 is a deficient number, since it is larger than the sum of its proper divisors (1206919736).

1216422784 is an frugal number, since it uses more digits than its factorization.

1216422784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9503317 (or 9503305 counting only the distinct ones).

The product of its digits is 43008, while the sum is 37.

The square root of 1216422784 is about 34877.2531028463. The cubic root of 1216422784 is about 1067.4843466379.

The spelling of 1216422784 in words is "one billion, two hundred sixteen million, four hundred twenty-two thousand, seven hundred eighty-four".