3971355869 has 4 divisors (see below), whose sum is σ = 4276844796. Its totient is φ = 3665866944.

The previous prime is 3971355853. The next prime is 3971355877. The reversal of 3971355869 is 9685531793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9685531793 = 7 ⋅1383647399.

It can be written as a sum of positive squares in 2 ways, for example, as 2658742969 + 1312612900 = 51563^2 + 36230^2 .

It is a cyclic number.

It is not a de Polignac number, because 3971355869 - 2⁴ = 3971355853 is a prime.

It is a super-2 number, since 2×3971355869² = 31543334876481490322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3971355169) 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, 152744444 + ... + 152744469.

It is an arithmetic number, because the mean of its divisors is an integer number (1069211199).

Almost surely, 2^3971355869 is an apocalyptic number.

It is an amenable number.

3971355869 is a deficient number, since it is larger than the sum of its proper divisors (305488927).

3971355869 is a wasteful number, since it uses less digits than its factorization.

3971355869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305488926.

The product of its digits is 6123600, while the sum is 56.

The square root of 3971355869 is about 63018.6945993012. The cubic root of 3971355869 is about 1583.6028274450.

The spelling of 3971355869 in words is "three billion, nine hundred seventy-one million, three hundred fifty-five thousand, eight hundred sixty-nine".