651689620 has 12 divisors (see below), whose sum is σ = 1368548244. Its totient is φ = 260675840.

The previous prime is 651689609. The next prime is 651689641. The reversal of 651689620 is 26986156.

It can be written as a sum of positive squares in 2 ways, for example, as 412739856 + 238949764 = 20316^2 + 15458^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16292221 + ... + 16292260.

It is an arithmetic number, because the mean of its divisors is an integer number (114045687).

Almost surely, 2^651689620 is an apocalyptic number.

It is an amenable number.

651689620 is an abundant number, since it is smaller than the sum of its proper divisors (716858624).

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

651689620 is a wasteful number, since it uses less digits than its factorization.

651689620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32584490 (or 32584488 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 651689620 is about 25528.2122366608. The cubic root of 651689620 is about 866.9890276816.

The spelling of 651689620 in words is "six hundred fifty-one million, six hundred eighty-nine thousand, six hundred twenty".