1380649 has 4 divisors (see below), whose sum is σ = 1399636. Its totient is φ = 1361664.

The previous prime is 1380637. The next prime is 1380653. The reversal of 1380649 is 9460831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9460831 = 733 ⋅12907.

It can be written as a sum of positive squares in 2 ways, for example, as 1123600 + 257049 = 1060^2 + 507^2 .

It is a cyclic number.

It is not a de Polignac number, because 1380649 - 2¹⁵ = 1347881 is a prime.

It is a super-2 number, since 2×1380649² = 3812383322402, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1380649.

It is not an unprimeable number, because it can be changed into a prime (1380619) 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, 9384 + ... + 9529.

It is an arithmetic number, because the mean of its divisors is an integer number (349909).

2^1380649 is an apocalyptic number.

It is an amenable number.

1380649 is a deficient number, since it is larger than the sum of its proper divisors (18987).

1380649 is an equidigital number, since it uses as much as digits as its factorization.

1380649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18986.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1380649 is about 1175.0102127216. The cubic root of 1380649 is about 111.3510784421.

The spelling of 1380649 in words is "one million, three hundred eighty thousand, six hundred forty-nine".