1378891749 has 8 divisors (see below), whose sum is σ = 1897829632. Its totient is φ = 889607520.

The previous prime is 1378891741. The next prime is 1378891757. The reversal of 1378891749 is 9471988731.

It is an interprime number because it is at equal distance from previous prime (1378891741) and next prime (1378891757).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1378891749 - 2³ = 1378891741 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378891741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7413304 + ... + 7413489.

It is an arithmetic number, because the mean of its divisors is an integer number (237228704).

Almost surely, 2^1378891749 is an apocalyptic number.

It is an amenable number.

1378891749 is a deficient number, since it is larger than the sum of its proper divisors (518937883).

1378891749 is a wasteful number, since it uses less digits than its factorization.

1378891749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14826827.

The product of its digits is 3048192, while the sum is 57.

The square root of 1378891749 is about 37133.4316889781. The cubic root of 1378891749 is about 1113.0381688422.

The spelling of 1378891749 in words is "one billion, three hundred seventy-eight million, eight hundred ninety-one thousand, seven hundred forty-nine".