1216440157 has 8 divisors (see below), whose sum is σ = 1252478936. Its totient is φ = 1180567872.

The previous prime is 1216440143. The next prime is 1216440221. The reversal of 1216440157 is 7510446121.

It can be written as a sum of positive squares in 4 ways, for example, as 656691876 + 559748281 = 25626^2 + 23659^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1216440157 - 2¹⁵ = 1216407389 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 (1216440107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26718 + ... + 56095.

It is an arithmetic number, because the mean of its divisors is an integer number (156559867).

Almost surely, 2^1216440157 is an apocalyptic number.

It is an amenable number.

1216440157 is a deficient number, since it is larger than the sum of its proper divisors (36038779).

1216440157 is an equidigital number, since it uses as much as digits as its factorization.

1216440157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83247.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 1216440157 is about 34877.5021611353. The cubic root of 1216440157 is about 1067.4894285655.

Adding to 1216440157 its reverse (7510446121), we get a palindrome (8726886278).

The spelling of 1216440157 in words is "one billion, two hundred sixteen million, four hundred forty thousand, one hundred fifty-seven".