1216231465 has 16 divisors (see below), whose sum is σ = 1498233600. Its totient is φ = 947486592.

The previous prime is 1216231433. The next prime is 1216231529. The reversal of 1216231465 is 5641326121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1216231465 - 2⁵ = 1216231433 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7746 + ... + 49924.

It is an arithmetic number, because the mean of its divisors is an integer number (93639600).

Almost surely, 2^1216231465 is an apocalyptic number.

It is an amenable number.

1216231465 is a deficient number, since it is larger than the sum of its proper divisors (282002135).

1216231465 is an equidigital number, since it uses as much as digits as its factorization.

1216231465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42336.

The product of its digits is 8640, while the sum is 31.

The square root of 1216231465 is about 34874.5102474572. The cubic root of 1216231465 is about 1067.4283790505.

Adding to 1216231465 its reverse (5641326121), we get a palindrome (6857557586).

The spelling of 1216231465 in words is "one billion, two hundred sixteen million, two hundred thirty-one thousand, four hundred sixty-five".