3721405645 has 16 divisors (see below), whose sum is σ = 4704120000. Its totient is φ = 2818395648.

The previous prime is 3721405643. The next prime is 3721405691. The reversal of 3721405645 is 5465041273.

3721405645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 3721405645 - 2¹ = 3721405643 is a prime.

It is a super-3 number, since 3×3721405645³ (a number of 30 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3721405643) 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, 125181 + ... + 152029.

It is an arithmetic number, because the mean of its divisors is an integer number (294007500).

Almost surely, 2^3721405645 is an apocalyptic number.

It is an amenable number.

3721405645 is a deficient number, since it is larger than the sum of its proper divisors (982714355).

3721405645 is a wasteful number, since it uses less digits than its factorization.

3721405645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28332.

The product of its (nonzero) digits is 100800, while the sum is 37.

The square root of 3721405645 is about 61003.3248684037. The cubic root of 3721405645 is about 1549.6573151547.

The spelling of 3721405645 in words is "three billion, seven hundred twenty-one million, four hundred five thousand, six hundred forty-five".