3721872640 has 36 divisors (see below), whose sum is σ = 8915051124. Its totient is φ = 1488748544.

The previous prime is 3721872629. The next prime is 3721872647. The reversal of 3721872640 is 462781273.

It can be written as a sum of positive squares in 2 ways, for example, as 605553664 + 3116318976 = 24608^2 + 55824^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 3721872593 and 3721872602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3721872647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1452577 + ... + 1455136.

It is an arithmetic number, because the mean of its divisors is an integer number (247640309).

Almost surely, 2^3721872640 is an apocalyptic number.

It is an amenable number.

3721872640 is an abundant number, since it is smaller than the sum of its proper divisors (5193178484).

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

3721872640 is an equidigital number, since it uses as much as digits as its factorization.

3721872640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2907734 (or 2907720 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 40.

The square root of 3721872640 is about 61007.1523675708. The cubic root of 3721872640 is about 1549.7221340267.

The spelling of 3721872640 in words is "three billion, seven hundred twenty-one million, eight hundred seventy-two thousand, six hundred forty".