688364381 has 4 divisors (see below), whose sum is σ = 689409600. Its totient is φ = 687319164.

The previous prime is 688364363. The next prime is 688364399. The reversal of 688364381 is 183463886.

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 an interprime number because it is at equal distance from previous prime (688364363) and next prime (688364399).

It is a cyclic number.

It is not a de Polignac number, because 688364381 - 2¹⁸ = 688102237 is a prime.

It is a super-2 number, since 2×688364381² = 947691042059026322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688364351) 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, 521621 + ... + 522938.

It is an arithmetic number, because the mean of its divisors is an integer number (172352400).

Almost surely, 2^688364381 is an apocalyptic number.

It is an amenable number.

688364381 is a deficient number, since it is larger than the sum of its proper divisors (1045219).

688364381 is a wasteful number, since it uses less digits than its factorization.

688364381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045218.

The product of its digits is 663552, while the sum is 47.

The square root of 688364381 is about 26236.6991254616. The cubic root of 688364381 is about 882.9568157133.

The spelling of 688364381 in words is "six hundred eighty-eight million, three hundred sixty-four thousand, three hundred eighty-one".