1291898216 has 64 divisors (see below), whose sum is σ = 2935034880. Its totient is φ = 521303040.

The previous prime is 1291898213. The next prime is 1291898219. The reversal of 1291898216 is 6128981921.

It is an interprime number because it is at equal distance from previous prime (1291898213) and next prime (1291898219).

It is not an unprimeable number, because it can be changed into a prime (1291898213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54176 + ... + 74288.

It is an arithmetic number, because the mean of its divisors is an integer number (45859920).

Almost surely, 2^1291898216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1291898216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1467517440).

1291898216 is an abundant number, since it is smaller than the sum of its proper divisors (1643136664).

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

1291898216 is a wasteful number, since it uses less digits than its factorization.

1291898216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20194 (or 20190 counting only the distinct ones).

The product of its digits is 124416, while the sum is 47.

The square root of 1291898216 is about 35942.9856300224. The cubic root of 1291898216 is about 1089.1209184621.

The spelling of 1291898216 in words is "one billion, two hundred ninety-one million, eight hundred ninety-eight thousand, two hundred sixteen".