1321215144 has 32 divisors (see below), whose sum is σ = 3349563840. Its totient is φ = 434201600.

The previous prime is 1321215139. The next prime is 1321215149. The reversal of 1321215144 is 4415121231.

It is an interprime number because it is at equal distance from previous prime (1321215139) and next prime (1321215149).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (1321215149) 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 7 ways as a sum of consecutive naturals, for example, 385977 + ... + 389384.

It is an arithmetic number, because the mean of its divisors is an integer number (104673870).

Almost surely, 2^1321215144 is an apocalyptic number.

It is an amenable number.

1321215144 is an abundant number, since it is smaller than the sum of its proper divisors (2028348696).

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

1321215144 is a wasteful number, since it uses less digits than its factorization.

1321215144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 775441 (or 775437 counting only the distinct ones).

The product of its digits is 960, while the sum is 24.

The square root of 1321215144 is about 36348.5232712417. The cubic root of 1321215144 is about 1097.2978148141.

Adding to 1321215144 its reverse (4415121231), we get a palindrome (5736336375).

The spelling of 1321215144 in words is "one billion, three hundred twenty-one million, two hundred fifteen thousand, one hundred forty-four".