1023691 has 4 divisors (see below), whose sum is σ = 1026000. Its totient is φ = 1021384.

The previous prime is 1023653. The next prime is 1023697. The reversal of 1023691 is 1963201.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1023691 - 2¹³ = 1015499 is a prime.

It is a Duffinian number.

1023691 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1023697) 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, 256 + ... + 1453.

It is an arithmetic number, because the mean of its divisors is an integer number (256500).

2^1023691 is an apocalyptic number.

1023691 is a deficient number, since it is larger than the sum of its proper divisors (2309).

1023691 is an equidigital number, since it uses as much as digits as its factorization.

1023691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2308.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1023691 is about 1011.7761610159. The cubic root of 1023691 is about 100.7835445444.

Adding to 1023691 its reverse (1963201), we get a palindrome (2986892).

The spelling of 1023691 in words is "one million, twenty-three thousand, six hundred ninety-one".