1397820 has 24 divisors (see below), whose sum is σ = 3914064. Its totient is φ = 372736.

The previous prime is 1397783. The next prime is 1397833. The reversal of 1397820 is 287931.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

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, 11589 + ... + 11708.

It is an arithmetic number, because the mean of its divisors is an integer number (163086).

2^1397820 is an apocalyptic number.

1397820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1397820 is an abundant number, since it is smaller than the sum of its proper divisors (2516244).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1397820 is a wasteful number, since it uses less digits than its factorization.

1397820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23309 (or 23307 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 1397820 is about 1182.2943795857. The cubic root of 1397820 is about 111.8107987602.

The spelling of 1397820 in words is "one million, three hundred ninety-seven thousand, eight hundred twenty".