1626230981 has 2 divisors, whose sum is σ = 1626230982. Its totient is φ = 1626230980.

The previous prime is 1626230971. The next prime is 1626231017. The reversal of 1626230981 is 1890326261.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1250258881 + 375972100 = 35359^2 + 19390^2 .

It is an emirp because it is prime and its reverse (1890326261) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1626230981 is a prime.

It is a super-2 number, since 2×1626230981² = 5289254407128444722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1626230911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 813115490 + 813115491.

It is an arithmetic number, because the mean of its divisors is an integer number (813115491).

Almost surely, 2^1626230981 is an apocalyptic number.

It is an amenable number.

1626230981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1626230981 is an equidigital number, since it uses as much as digits as its factorization.

1626230981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 1626230981 is about 40326.5542911863. The cubic root of 1626230981 is about 1175.9641354254.

The spelling of 1626230981 in words is "one billion, six hundred twenty-six million, two hundred thirty thousand, nine hundred eighty-one".