687492405 has 12 divisors (see below), whose sum is σ = 1191653580. Its totient is φ = 366662592.

The previous prime is 687492401. The next prime is 687492419. The reversal of 687492405 is 504294786.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 200760561 + 486731844 = 14169^2 + 22062^2 .

It is not a de Polignac number, because 687492405 - 2² = 687492401 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 15277609 = 687492405 / (6 + 8 + 7 + 4 + 9 + 2 + 4 + 0 + 5).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687492401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7638760 + ... + 7638849.

It is an arithmetic number, because the mean of its divisors is an integer number (99304465).

Almost surely, 2^687492405 is an apocalyptic number.

It is an amenable number.

687492405 is a deficient number, since it is larger than the sum of its proper divisors (504161175).

687492405 is a wasteful number, since it uses less digits than its factorization.

687492405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15277620 (or 15277617 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 687492405 is about 26220.0763728865. The cubic root of 687492405 is about 882.5838337595.

The spelling of 687492405 in words is "six hundred eighty-seven million, four hundred ninety-two thousand, four hundred five".