1213890816 has 72 divisors (see below), whose sum is σ = 3342185280. Its totient is φ = 390670336.

The previous prime is 1213890809. The next prime is 1213890859. The reversal of 1213890816 is 6180983121.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4980 + ... + 49523.

It is an arithmetic number, because the mean of its divisors is an integer number (46419240).

Almost surely, 2^1213890816 is an apocalyptic number.

1213890816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1213890816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1671092640).

1213890816 is an abundant number, since it is smaller than the sum of its proper divisors (2128294464).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1213890816 is an equidigital number, since it uses as much as digits as its factorization.

1213890816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54551 (or 54537 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 39.

The square root of 1213890816 is about 34840.9359231350. The cubic root of 1213890816 is about 1066.7431806225.

The spelling of 1213890816 in words is "one billion, two hundred thirteen million, eight hundred ninety thousand, eight hundred sixteen".