1961378 has 4 divisors (see below), whose sum is σ = 2942070. Its totient is φ = 980688.

The previous prime is 1961363. The next prime is 1961381. The reversal of 1961378 is 8731691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8731691 = 479 ⋅18229.

It can be written as a sum of positive squares in only one way, i.e., 1216609 + 744769 = 1103^2 + 863^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490343 + ... + 490346.

2^1961378 is an apocalyptic number.

1961378 is a deficient number, since it is larger than the sum of its proper divisors (980692).

1961378 is an equidigital number, since it uses as much as digits as its factorization.

1961378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980691.

The product of its digits is 9072, while the sum is 35.

The square root of 1961378 is about 1400.4920563859. The cubic root of 1961378 is about 125.1758165923.

It can be divided in two parts, 19613 and 78, that added together give a palindrome (19691).

The spelling of 1961378 in words is "one million, nine hundred sixty-one thousand, three hundred seventy-eight".