3765281664 has 64 divisors (see below), whose sum is σ = 10015514640. Its totient is φ = 1253339136.

The previous prime is 3765281659. The next prime is 3765281687. The reversal of 3765281664 is 4661825673.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 284212 + ... + 297164.

Almost surely, 2^3765281664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3765281664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5007757320).

3765281664 is an abundant number, since it is smaller than the sum of its proper divisors (6250232976).

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

3765281664 is a wasteful number, since it uses less digits than its factorization.

3765281664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13727 (or 13715 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 48.

The square root of 3765281664 is about 61361.8909747736. The cubic root of 3765281664 is about 1555.7237786809.

It can be divided in two parts, 37652 and 81664, that added together give a triangular number (119316 = T₄₈₈).

The spelling of 3765281664 in words is "three billion, seven hundred sixty-five million, two hundred eighty-one thousand, six hundred sixty-four".