651144640 has 28 divisors (see below), whose sum is σ = 1550538936. Its totient is φ = 260457728.

The previous prime is 651144629. The next prime is 651144643. The reversal of 651144640 is 46441156.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651144643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1017094 + ... + 1017733.

Almost surely, 2^651144640 is an apocalyptic number.

It is an amenable number.

651144640 is an abundant number, since it is smaller than the sum of its proper divisors (899394296).

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

651144640 is a wasteful number, since it uses less digits than its factorization.

651144640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2034844 (or 2034834 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 651144640 is about 25517.5359311984. The cubic root of 651144640 is about 866.7472850712.

Adding to 651144640 its reverse (46441156), we get a palindrome (697585796).

The spelling of 651144640 in words is "six hundred fifty-one million, one hundred forty-four thousand, six hundred forty".