1561216396 has 12 divisors (see below), whose sum is σ = 2875925080. Its totient is φ = 739523520.

The previous prime is 1561216381. The next prime is 1561216411. The reversal of 1561216396 is 6936121651.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1561216381) and next prime (1561216411).

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, 10271085 + ... + 10271236.

Almost surely, 2^1561216396 is an apocalyptic number.

It is an amenable number.

1561216396 is a deficient number, since it is larger than the sum of its proper divisors (1314708684).

1561216396 is a wasteful number, since it uses less digits than its factorization.

1561216396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20542344 (or 20542342 counting only the distinct ones).

The product of its digits is 58320, while the sum is 40.

The square root of 1561216396 is about 39512.2309671322. The cubic root of 1561216396 is about 1160.0793633771.

The spelling of 1561216396 in words is "one billion, five hundred sixty-one million, two hundred sixteen thousand, three hundred ninety-six".