688954935491 has 2 divisors, whose sum is σ = 688954935492. Its totient is φ = 688954935490.

The previous prime is 688954935481. The next prime is 688954935553. The reversal of 688954935491 is 194539459886.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 688954935491 - 2²² = 688950741187 is a prime.

It is a super-2 number, since 2×688954935491² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (688954935401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344477467745 + 344477467746.

It is an arithmetic number, because the mean of its divisors is an integer number (344477467746).

Almost surely, 2^688954935491 is an apocalyptic number.

688954935491 is a deficient number, since it is larger than the sum of its proper divisors (1).

688954935491 is an equidigital number, since it uses as much as digits as its factorization.

688954935491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 335923200, while the sum is 71.

The spelling of 688954935491 in words is "six hundred eighty-eight billion, nine hundred fifty-four million, nine hundred thirty-five thousand, four hundred ninety-one".