687631980 has 192 divisors, whose sum is σ = 2346624000. Its totient is φ = 146866176.

The previous prime is 687631979. The next prime is 687631981. The reversal of 687631980 is 89136786.

It is an interprime number because it is at equal distance from previous prime (687631979) and next prime (687631981).

It is not an unprimeable number, because it can be changed into a prime (687631981) 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 63 ways as a sum of consecutive naturals, for example, 1377771 + ... + 1378269.

It is an arithmetic number, because the mean of its divisors is an integer number (12222000).

Almost surely, 2^687631980 is an apocalyptic number.

687631980 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 687631980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1173312000).

687631980 is an abundant number, since it is smaller than the sum of its proper divisors (1658992020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

687631980 is a wasteful number, since it uses less digits than its factorization.

687631980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728 (or 726 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 48.

The square root of 687631980 is about 26222.7378433298. The cubic root of 687631980 is about 882.6435572329.

The spelling of 687631980 in words is "six hundred eighty-seven million, six hundred thirty-one thousand, nine hundred eighty".