3621547845 has 18 divisors (see below), whose sum is σ = 6278049414. Its totient is φ = 1931276880.

The previous prime is 3621547841. The next prime is 3621547873. The reversal of 3621547845 is 5487451263.

3621547845 is a `hidden beast` number, since 3 + 6 + 21 + 547 + 84 + 5 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2897238276 + 724309569 = 53826^2 + 26913^2 .

It is not a de Polignac number, because 3621547845 - 2² = 3621547841 is a prime.

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

It is a self number, because there is not a number n which added to its sum of digits gives 3621547845.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3621547841) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 399210 + ... + 408180.

It is an arithmetic number, because the mean of its divisors is an integer number (348780523).

Almost surely, 2^3621547845 is an apocalyptic number.

It is an amenable number.

3621547845 is a deficient number, since it is larger than the sum of its proper divisors (2656501569).

3621547845 is an frugal number, since it uses more digits than its factorization.

3621547845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17953 (or 8979 counting only the distinct ones).

The product of its digits is 806400, while the sum is 45.

The square root of 3621547845 is about 60179.2974784518. The cubic root of 3621547845 is about 1535.6706205453.

Multiplying 3621547845 by its sum of digits (45), we get a square (162969653025 = 403695²).

3621547845 divided by its sum of digits (45) gives a square (80478841 = 8971²).

The spelling of 3621547845 in words is "three billion, six hundred twenty-one million, five hundred forty-seven thousand, eight hundred forty-five".