16861388507 has 2 divisors, whose sum is σ = 16861388508. Its totient is φ = 16861388506.

The previous prime is 16861388491. The next prime is 16861388521. The reversal of 16861388507 is 70588316861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16861388507 - 2⁴ = 16861388491 is a prime.

It is not a weakly prime, because it can be changed into another prime (16861388567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8430694253 + 8430694254.

It is an arithmetic number, because the mean of its divisors is an integer number (8430694254).

Almost surely, 2^16861388507 is an apocalyptic number.

16861388507 is a deficient number, since it is larger than the sum of its proper divisors (1).

16861388507 is an equidigital number, since it uses as much as digits as its factorization.

16861388507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1935360, while the sum is 53.

The spelling of 16861388507 in words is "sixteen billion, eight hundred sixty-one million, three hundred eighty-eight thousand, five hundred seven".