1997378 has 4 divisors (see below), whose sum is σ = 2996070. Its totient is φ = 998688.

The previous prime is 1997351. The next prime is 1997407. The reversal of 1997378 is 8737991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8737991 = 83 ⋅105277.

It can be written as a sum of positive squares in only one way, i.e., 1352569 + 644809 = 1163^2 + 803^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499343 + ... + 499346.

2^1997378 is an apocalyptic number.

1997378 is a deficient number, since it is larger than the sum of its proper divisors (998692).

1997378 is an equidigital number, since it uses as much as digits as its factorization.

1997378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998691.

The product of its digits is 95256, while the sum is 44.

The square root of 1997378 is about 1413.2862413538. The cubic root of 1997378 is about 125.9370223615.

The spelling of 1997378 in words is "one million, nine hundred ninety-seven thousand, three hundred seventy-eight".