1378690 has 8 divisors (see below), whose sum is σ = 2481660. Its totient is φ = 551472.

The previous prime is 1378681. The next prime is 1378691. The reversal of 1378690 is 968731.

It can be written as a sum of positive squares in 2 ways, for example, as 1194649 + 184041 = 1093^2 + 429^2 .

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

It is a super-2 number, since 2×1378690² = 3801572232200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1378691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68925 + ... + 68944.

2^1378690 is an apocalyptic number.

1378690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1378690 is a deficient number, since it is larger than the sum of its proper divisors (1102970).

1378690 is a wasteful number, since it uses less digits than its factorization.

1378690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137876.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 1378690 is about 1174.1763070340. The cubic root of 1378690 is about 111.2983882422.

The spelling of 1378690 in words is "one million, three hundred seventy-eight thousand, six hundred ninety".