1291216464 has 140 divisors (see below), whose sum is σ = 3872962432. Its totient is φ = 416404800.

The previous prime is 1291216447. The next prime is 1291216469. The reversal of 1291216464 is 4646121921.

1291216464 is a `hidden beast` number, since 1 + 2 + 9 + 1 + 2 + 1 + 646 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291216469) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 359799 + ... + 363369.

Almost surely, 2^1291216464 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 1291216464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1936481216).

1291216464 is an abundant number, since it is smaller than the sum of its proper divisors (2581745968).

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

1291216464 is an equidigital number, since it uses as much as digits as its factorization.

1291216464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3628 (or 3607 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 1291216464 is about 35933.5005809342. The cubic root of 1291216464 is about 1088.9293035179.

The spelling of 1291216464 in words is "one billion, two hundred ninety-one million, two hundred sixteen thousand, four hundred sixty-four".