686760731421 has 8 divisors (see below), whose sum is σ = 924081718560. Its totient is φ = 453640115952.

The previous prime is 686760731417. The next prime is 686760731429. The reversal of 686760731421 is 124137067686.

It is a happy number.

686760731421 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 686760731421 - 2² = 686760731417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686760731429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1050092535 + ... + 1050093188.

It is an arithmetic number, because the mean of its divisors is an integer number (115510214820).

Almost surely, 2^686760731421 is an apocalyptic number.

It is an amenable number.

686760731421 is a deficient number, since it is larger than the sum of its proper divisors (237320987139).

686760731421 is a wasteful number, since it uses less digits than its factorization.

686760731421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100185835.

The product of its (nonzero) digits is 2032128, while the sum is 51.

The spelling of 686760731421 in words is "six hundred eighty-six billion, seven hundred sixty million, seven hundred thirty-one thousand, four hundred twenty-one".