1235981 has 2 divisors, whose sum is σ = 1235982. Its totient is φ = 1235980.

The previous prime is 1235977. The next prime is 1235987. The reversal of 1235981 is 1895321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 697225 + 538756 = 835^2 + 734^2 .

It is an emirp because it is prime and its reverse (1895321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1235981 - 2² = 1235977 is a prime.

It is a super-2 number, since 2×1235981² = 3055298064722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1235987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 617990 + 617991.

It is an arithmetic number, because the mean of its divisors is an integer number (617991).

2^1235981 is an apocalyptic number.

It is an amenable number.

1235981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1235981 is an equidigital number, since it uses as much as digits as its factorization.

1235981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 29.

The square root of 1235981 is about 1111.7468236968. The cubic root of 1235981 is about 107.3175126389.

The spelling of 1235981 in words is "one million, two hundred thirty-five thousand, nine hundred eighty-one".