6691738687629 has 4 divisors (see below), whose sum is σ = 8922318250176. Its totient is φ = 4461159125084.

The previous prime is 6691738687609. The next prime is 6691738687639. The reversal of 6691738687629 is 9267868371966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6691738687629 - 2⁸ = 6691738687373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6691738687609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1115289781269 + ... + 1115289781274.

It is an arithmetic number, because the mean of its divisors is an integer number (2230579562544).

Almost surely, 2^{6691738687629} is an apocalyptic number.

It is an amenable number.

6691738687629 is a deficient number, since it is larger than the sum of its proper divisors (2230579562547).

6691738687629 is a wasteful number, since it uses less digits than its factorization.

6691738687629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2230579562546.

The product of its digits is 1975228416, while the sum is 78.

The spelling of 6691738687629 in words is "six trillion, six hundred ninety-one billion, seven hundred thirty-eight million, six hundred eighty-seven thousand, six hundred twenty-nine".