687009421 has 8 divisors (see below), whose sum is σ = 791336960. Its totient is φ = 584227728.

The previous prime is 687009413. The next prime is 687009431. The reversal of 687009421 is 124900786.

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

It is not a de Polignac number, because 687009421 - 2³ = 687009413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687009431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 385506 + ... + 387283.

It is an arithmetic number, because the mean of its divisors is an integer number (98917120).

Almost surely, 2^687009421 is an apocalyptic number.

It is an amenable number.

687009421 is a deficient number, since it is larger than the sum of its proper divisors (104327539).

687009421 is a wasteful number, since it uses less digits than its factorization.

687009421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772923.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 687009421 is about 26210.8645603307. The cubic root of 687009421 is about 882.3771048174.

The spelling of 687009421 in words is "six hundred eighty-seven million, nine thousand, four hundred twenty-one".