1397890 has 16 divisors (see below), whose sum is σ = 2710008. Its totient is φ = 516096.

The previous prime is 1397881. The next prime is 1397909. The reversal of 1397890 is 987931.

It can be written as a sum of positive squares in 4 ways, for example, as 1203409 + 194481 = 1097^2 + 441^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5247 + ... + 5506.

2^1397890 is an apocalyptic number.

1397890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1397890 is a deficient number, since it is larger than the sum of its proper divisors (1312118).

1397890 is a wasteful number, since it uses less digits than its factorization.

1397890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10773.

The product of its (nonzero) digits is 13608, while the sum is 37.

The square root of 1397890 is about 1182.3239826714. The cubic root of 1397890 is about 111.8126651486.

It can be divided in two parts, 13 and 97890, that added together give a triangular number (97903 = T₄₄₂).

The spelling of 1397890 in words is "one million, three hundred ninety-seven thousand, eight hundred ninety".