1321545040 has 80 divisors (see below), whose sum is σ = 3214044288. Its totient is φ = 504396288.

The previous prime is 1321545023. The next prime is 1321545047. The reversal of 1321545040 is 405451231.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1321544996 and 1321545014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321545047) 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, 1182562 + ... + 1183678.

Almost surely, 2^1321545040 is an apocalyptic number.

1321545040 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 1321545040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1607022144).

1321545040 is an abundant number, since it is smaller than the sum of its proper divisors (1892499248).

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

1321545040 is a wasteful number, since it uses less digits than its factorization.

1321545040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1796 (or 1790 counting only the distinct ones).

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

The square root of 1321545040 is about 36353.0609440251. The cubic root of 1321545040 is about 1097.3891358067.

Adding to 1321545040 its reverse (405451231), we get a palindrome (1726996271).

The spelling of 1321545040 in words is "one billion, three hundred twenty-one million, five hundred forty-five thousand, forty".