1215354400 has 144 divisors (see below), whose sum is σ = 3222309384. Its totient is φ = 444948480.

The previous prime is 1215354391. The next prime is 1215354401. The reversal of 1215354400 is 44535121.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 35569296 + 1179785104 = 5964^2 + 34348^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (1215354401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1424374 + ... + 1425226.

Almost surely, 2^1215354400 is an apocalyptic number.

1215354400 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 1215354400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1611154692).

1215354400 is an abundant number, since it is smaller than the sum of its proper divisors (2006954984).

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

1215354400 is a wasteful number, since it uses less digits than its factorization.

1215354400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1023 (or 1010 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 1215354400 is about 34861.9333944634. The cubic root of 1215354400 is about 1067.1717313012.

Adding to 1215354400 its reverse (44535121), we get a palindrome (1259889521).

The spelling of 1215354400 in words is "one billion, two hundred fifteen million, three hundred fifty-four thousand, four hundred".