1645581960 has 128 divisors (see below), whose sum is σ = 5983977600. Its totient is φ = 398926080.

The previous prime is 1645581937. The next prime is 1645581961. The reversal of 1645581960 is 691855461.

1645581960 is a `hidden beast` number, since 1 + 6 + 4 + 5 + 581 + 9 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1645581961) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 57379 + ... + 81138.

It is an arithmetic number, because the mean of its divisors is an integer number (46749825).

Almost surely, 2^1645581960 is an apocalyptic number.

1645581960 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1645581960 is an abundant number, since it is smaller than the sum of its proper divisors (4338395640).

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

1645581960 is a wasteful number, since it uses less digits than its factorization.

1645581960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138548 (or 138538 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 45.

The square root of 1645581960 is about 40565.7732577600. The cubic root of 1645581960 is about 1180.6101316600.

The spelling of 1645581960 in words is "one billion, six hundred forty-five million, five hundred eighty-one thousand, nine hundred sixty".