1396778 has 12 divisors (see below), whose sum is σ = 2149602. Its totient is φ = 680520.

The previous prime is 1396757. The next prime is 1396789. The reversal of 1396778 is 8776931.

1396778 = 57² + 58² + ... + 163².

It can be written as a sum of positive squares in only one way, i.e., 1385329 + 11449 = 1177^2 + 107^2 .

It is an Ulam number.

It is a zygodrome in base 4.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13001 + ... + 13107.

2^1396778 is an apocalyptic number.

1396778 is a deficient number, since it is larger than the sum of its proper divisors (752824).

1396778 is an equidigital number, since it uses as much as digits as its factorization.

1396778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277 (or 170 counting only the distinct ones).

The product of its digits is 63504, while the sum is 41.

The square root of 1396778 is about 1181.8536288390. The cubic root of 1396778 is about 111.7830088649.

The spelling of 1396778 in words is "one million, three hundred ninety-six thousand, seven hundred seventy-eight".