3720781249 has 4 divisors (see below), whose sum is σ = 3728852820. Its totient is φ = 3712709680.

The previous prime is 3720781247. The next prime is 3720781303. The reversal of 3720781249 is 9421870273.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9421870273 = 4517 ⋅2085869.

It can be written as a sum of positive squares in 2 ways, for example, as 368371249 + 3352410000 = 19193^2 + 57900^2 .

It is a cyclic number.

It is not a de Polignac number, because 3720781249 - 2¹ = 3720781247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3720781243) 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, 4035094 + ... + 4036015.

It is an arithmetic number, because the mean of its divisors is an integer number (932213205).

Almost surely, 2^3720781249 is an apocalyptic number.

It is an amenable number.

3720781249 is a deficient number, since it is larger than the sum of its proper divisors (8071571).

3720781249 is an equidigital number, since it uses as much as digits as its factorization.

3720781249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8071570.

The product of its (nonzero) digits is 169344, while the sum is 43.

The square root of 3720781249 is about 60998.2069326632. The cubic root of 3720781249 is about 1549.5706405624.

The spelling of 3720781249 in words is "three billion, seven hundred twenty million, seven hundred eighty-one thousand, two hundred forty-nine".