1913681 has 16 divisors (see below), whose sum is σ = 2471040. Its totient is φ = 1438080.

The previous prime is 1913651. The next prime is 1913683. The reversal of 1913681 is 1863191.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1913681 is a prime.

It is a super-2 number, since 2×1913681² = 7324349939522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is not an unprimeable number, because it can be changed into a prime (1913683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1805 + ... + 2661.

It is an arithmetic number, because the mean of its divisors is an integer number (154440).

2^1913681 is an apocalyptic number.

1913681 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1913681 is a deficient number, since it is larger than the sum of its proper divisors (557359).

1913681 is a wasteful number, since it uses less digits than its factorization.

1913681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904.

The product of its digits is 1296, while the sum is 29.

The square root of 1913681 is about 1383.3585941469. The cubic root of 1913681 is about 124.1527989757.

The spelling of 1913681 in words is "one million, nine hundred thirteen thousand, six hundred eighty-one".