3645878985 has 128 divisors (see below), whose sum is σ = 7717248000. Its totient is φ = 1597833216.

The previous prime is 3645878983. The next prime is 3645878987. The reversal of 3645878985 is 5898785463.

3645878985 is a `hidden beast` number, since 36 + 458 + 78 + 9 + 85 = 666.

It is an interprime number because it is at equal distance from previous prime (3645878983) and next prime (3645878987).

It is not a de Polignac number, because 3645878985 - 2¹ = 3645878983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3645878983) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4740681 + ... + 4741449.

It is an arithmetic number, because the mean of its divisors is an integer number (60291000).

Almost surely, 2^3645878985 is an apocalyptic number.

3645878985 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

3645878985 is an abundant number, since it is smaller than the sum of its proper divisors (4071369015).

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

3645878985 is a wasteful number, since it uses less digits than its factorization.

3645878985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992 (or 986 counting only the distinct ones).

The product of its digits is 58060800, while the sum is 63.

The square root of 3645878985 is about 60381.1144729873. The cubic root of 3645878985 is about 1539.1020493263.

The spelling of 3645878985 in words is "three billion, six hundred forty-five million, eight hundred seventy-eight thousand, nine hundred eighty-five".