651064686138 has 128 divisors (see below), whose sum is σ = 1542576752640. Its totient is φ = 202839310080.

The previous prime is 651064686137. The next prime is 651064686143. The reversal of 651064686138 is 831686460156.

651064686138 is a `hidden beast` number, since 6 + 5 + 10 + 6 + 4 + 6 + 8 + 613 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (651064686137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 79910581 + ... + 79918727.

It is an arithmetic number, because the mean of its divisors is an integer number (12051380880).

Almost surely, 2^651064686138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 651064686138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (771288376320).

651064686138 is an abundant number, since it is smaller than the sum of its proper divisors (891512066502).

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

651064686138 is a wasteful number, since it uses less digits than its factorization.

651064686138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8769 (or 8763 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 651064686138 in words is "six hundred fifty-one billion, sixty-four million, six hundred eighty-six thousand, one hundred thirty-eight".