1381720 has 16 divisors (see below), whose sum is σ = 3108960. Its totient is φ = 552672.

The previous prime is 1381697. The next prime is 1381727. The reversal of 1381720 is 271831.

It is a junction number, because it is equal to n+sod(n) for n = 1381691 and 1381700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17232 + ... + 17311.

It is an arithmetic number, because the mean of its divisors is an integer number (194310).

2^1381720 is an apocalyptic number.

1381720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1381720 is an abundant number, since it is smaller than the sum of its proper divisors (1727240).

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

1381720 is a wasteful number, since it uses less digits than its factorization.

1381720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34554 (or 34550 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 1381720 is about 1175.4658650935. The cubic root of 1381720 is about 111.3798634994.

The spelling of 1381720 in words is "one million, three hundred eighty-one thousand, seven hundred twenty".