687653421 has 16 divisors (see below), whose sum is σ = 1128457344. Its totient is φ = 362718144.

The previous prime is 687653413. The next prime is 687653443. The reversal of 687653421 is 124356786.

687653421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 687653421 - 2³ = 687653413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687653411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1259166 + ... + 1259711.

It is an arithmetic number, because the mean of its divisors is an integer number (70528584).

Almost surely, 2^687653421 is an apocalyptic number.

It is an amenable number.

687653421 is a deficient number, since it is larger than the sum of its proper divisors (440803923).

687653421 is a wasteful number, since it uses less digits than its factorization.

687653421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2518900.

The product of its digits is 241920, while the sum is 42.

The square root of 687653421 is about 26223.1466647311. The cubic root of 687653421 is about 882.6527310179.

The spelling of 687653421 in words is "six hundred eighty-seven million, six hundred fifty-three thousand, four hundred twenty-one".