1291982400 has 252 divisors, whose sum is σ = 4763518032. Its totient is φ = 344424960.

The previous prime is 1291982383. The next prime is 1291982401. The reversal of 1291982400 is 42891921.

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

It is not an unprimeable number, because it can be changed into a prime (1291982401) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 387139 + ... + 390461.

Almost surely, 2^1291982400 is an apocalyptic number.

1291982400 is a gapful number since it is divisible by the number (10) 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 1291982400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2381759016).

1291982400 is an abundant number, since it is smaller than the sum of its proper divisors (3471535632).

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

1291982400 is an equidigital number, since it uses as much as digits as its factorization.

1291982400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3360 (or 3333 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 1291982400 is about 35944.1566878401. The cubic root of 1291982400 is about 1089.1445747540.

The spelling of 1291982400 in words is "one billion, two hundred ninety-one million, nine hundred eighty-two thousand, four hundred".