651438144 has 126 divisors (see below), whose sum is σ = 2172177774. Its totient is φ = 186117120.

The previous prime is 651438143. The next prime is 651438157. The reversal of 651438144 is 441834156.

It can be written as a sum of positive squares in only one way, i.e., 553190400 + 98247744 = 23520^2 + 9912^2 .

It is a tau number, because it is divible by the number of its divisors (126).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 651438099 and 651438108.

It is not an unprimeable number, because it can be changed into a prime (651438143) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 16684 + ... + 39764.

Almost surely, 2^651438144 is an apocalyptic number.

651438144 is a gapful number since it is divisible by the number (64) 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 651438144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1086088887).

651438144 is an abundant number, since it is smaller than the sum of its proper divisors (1520739630).

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

651438144 is a wasteful number, since it uses less digits than its factorization.

651438144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23113 (or 23093 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 651438144 is about 25523.2863087809. The cubic root of 651438144 is about 866.8774945344.

The spelling of 651438144 in words is "six hundred fifty-one million, four hundred thirty-eight thousand, one hundred forty-four".