1321645446 has 48 divisors (see below), whose sum is σ = 3136964688. Its totient is φ = 398822400.

The previous prime is 1321645393. The next prime is 1321645447. The reversal of 1321645446 is 6445461231.

1321645446 is a `hidden beast` number, since 1 + 3 + 2 + 1 + 645 + 4 + 4 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1321645446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321645447) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33870 + ... + 61566.

It is an arithmetic number, because the mean of its divisors is an integer number (65353431).

Almost surely, 2^1321645446 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1321645446, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1568482344).

1321645446 is an abundant number, since it is smaller than the sum of its proper divisors (1815319242).

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

1321645446 is a wasteful number, since it uses less digits than its factorization.

1321645446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27957 (or 27954 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 1321645446 is about 36354.4419019189. The cubic root of 1321645446 is about 1097.4169269299.

The spelling of 1321645446 in words is "one billion, three hundred twenty-one million, six hundred forty-five thousand, four hundred forty-six".