1645332635544 has 64 divisors (see below), whose sum is σ = 4523991575040. Its totient is φ = 495484782720.

The previous prime is 1645332635539. The next prime is 1645332635549. The reversal of 1645332635544 is 4455362335461.

It is an interprime number because it is at equal distance from previous prime (1645332635539) and next prime (1645332635549).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645332635549) 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, 56086422 + ... + 56115749.

It is an arithmetic number, because the mean of its divisors is an integer number (70687368360).

Almost surely, 2^{1645332635544} is an apocalyptic number.

It is an amenable number.

1645332635544 is an abundant number, since it is smaller than the sum of its proper divisors (2878658939496).

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

1645332635544 is a wasteful number, since it uses less digits than its factorization.

1645332635544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112202240 (or 112202236 counting only the distinct ones).

The product of its digits is 15552000, while the sum is 51.

The spelling of 1645332635544 in words is "one trillion, six hundred forty-five billion, three hundred thirty-two million, six hundred thirty-five thousand, five hundred forty-four".