1913381 has 4 divisors (see below), whose sum is σ = 1965132. Its totient is φ = 1861632.

The previous prime is 1913377. The next prime is 1913389. The reversal of 1913381 is 1833191.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1833191 = 751 ⋅2441.

It can be written as a sum of positive squares in 2 ways, for example, as 1522756 + 390625 = 1234^2 + 625^2 .

It is a cyclic number.

It is not a de Polignac number, because 1913381 - 2² = 1913377 is a prime.

It is a super-2 number, since 2×1913381² = 7322053702322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1913381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1913389) 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, 25820 + ... + 25893.

It is an arithmetic number, because the mean of its divisors is an integer number (491283).

2^1913381 is an apocalyptic number.

It is an amenable number.

1913381 is a deficient number, since it is larger than the sum of its proper divisors (51751).

1913381 is an equidigital number, since it uses as much as digits as its factorization.

1913381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51750.

The product of its digits is 648, while the sum is 26.

The square root of 1913381 is about 1383.2501581420. The cubic root of 1913381 is about 124.1463109933.

The spelling of 1913381 in words is "one million, nine hundred thirteen thousand, three hundred eighty-one".