651981007 has 4 divisors (see below), whose sum is σ = 667143400. Its totient is φ = 636818616.

The previous prime is 651980999. The next prime is 651981047. The reversal of 651981007 is 700189156.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 651981007 - 2³ = 651980999 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 (651981047) 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 3 ways as a sum of consecutive naturals, for example, 7581132 + ... + 7581217.

It is an arithmetic number, because the mean of its divisors is an integer number (166785850).

Almost surely, 2^651981007 is an apocalyptic number.

651981007 is a deficient number, since it is larger than the sum of its proper divisors (15162393).

651981007 is a wasteful number, since it uses less digits than its factorization.

651981007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15162392.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 651981007 is about 25533.9187552557. The cubic root of 651981007 is about 867.1182260408.

The spelling of 651981007 in words is "six hundred fifty-one million, nine hundred eighty-one thousand, seven".