3870661645 has 4 divisors (see below), whose sum is σ = 4644793980. Its totient is φ = 3096529312.

The previous prime is 3870661607. The next prime is 3870661673. The reversal of 3870661645 is 5461660783.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5461660783 = 73 ⋅74817271.

It can be written as a sum of positive squares in 2 ways, for example, as 2339269956 + 1531391689 = 48366^2 + 39133^2 .

It is a cyclic number.

It is not a de Polignac number, because 3870661645 - 2¹³ = 3870653453 is a prime.

It is a super-3 number, since 3×3870661645³ (a number of 30 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 3870661595 and 3870661604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 387066160 + ... + 387066169.

It is an arithmetic number, because the mean of its divisors is an integer number (1161198495).

Almost surely, 2^3870661645 is an apocalyptic number.

It is an amenable number.

3870661645 is a deficient number, since it is larger than the sum of its proper divisors (774132335).

3870661645 is an equidigital number, since it uses as much as digits as its factorization.

3870661645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 774132334.

The product of its (nonzero) digits is 725760, while the sum is 46.

The square root of 3870661645 is about 62214.6417252402. The cubic root of 3870661645 is about 1570.1039385121.

The spelling of 3870661645 in words is "three billion, eight hundred seventy million, six hundred sixty-one thousand, six hundred forty-five".