1423991 has 2 divisors, whose sum is σ = 1423992. Its totient is φ = 1423990.

The previous prime is 1423979. The next prime is 1423997. The reversal of 1423991 is 1993241.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1993241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1423991 - 2¹⁴ = 1407607 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1423997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 711995 + 711996.

It is an arithmetic number, because the mean of its divisors is an integer number (711996).

2^1423991 is an apocalyptic number.

1423991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1423991 is an equidigital number, since it uses as much as digits as its factorization.

1423991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 29.

The square root of 1423991 is about 1193.3109401996. The cubic root of 1423991 is about 112.5042895484.

The spelling of 1423991 in words is "one million, four hundred twenty-three thousand, nine hundred ninety-one".