1377243649 has 4 divisors (see below), whose sum is σ = 1378058836. Its totient is φ = 1376428464.

The previous prime is 1377243641. The next prime is 1377243653. The reversal of 1377243649 is 9463427731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9463427731 = 643 ⋅14717617.

It can be written as a sum of positive squares in 2 ways, for example, as 420455025 + 956788624 = 20505^2 + 30932^2 .

It is a cyclic number.

It is not a de Polignac number, because 1377243649 - 2³ = 1377243641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1377243599 and 1377243608.

It is not an unprimeable number, because it can be changed into a prime (1377243641) 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, 405054 + ... + 408439.

It is an arithmetic number, because the mean of its divisors is an integer number (344514709).

Almost surely, 2^1377243649 is an apocalyptic number.

It is an amenable number.

1377243649 is a deficient number, since it is larger than the sum of its proper divisors (815187).

1377243649 is an equidigital number, since it uses as much as digits as its factorization.

1377243649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815186.

The product of its digits is 762048, while the sum is 46.

The square root of 1377243649 is about 37111.2334610425. The cubic root of 1377243649 is about 1112.5945445720.

The spelling of 1377243649 in words is "one billion, three hundred seventy-seven million, two hundred forty-three thousand, six hundred forty-nine".