17987649451 has 2 divisors, whose sum is σ = 17987649452. Its totient is φ = 17987649450.

The previous prime is 17987649443. The next prime is 17987649457. The reversal of 17987649451 is 15494678971.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 17987649451 - 2³ = 17987649443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 17987649451.

It is not a weakly prime, because it can be changed into another prime (17987649457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8993824725 + 8993824726.

It is an arithmetic number, because the mean of its divisors is an integer number (8993824726).

Almost surely, 2^17987649451 is an apocalyptic number.

17987649451 is a deficient number, since it is larger than the sum of its proper divisors (1).

17987649451 is an equidigital number, since it uses as much as digits as its factorization.

17987649451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15240960, while the sum is 61.

The spelling of 17987649451 in words is "seventeen billion, nine hundred eighty-seven million, six hundred forty-nine thousand, four hundred fifty-one".