65144500 has 48 divisors (see below), whose sum is σ = 143659152. Its totient is φ = 25804800.

The previous prime is 65144477. The next prime is 65144503. The reversal of 65144500 is 544156.

It can be written as a sum of positive squares in 8 ways, for example, as 32012964 + 33131536 = 5658^2 + 5756^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65144503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55924 + ... + 57076.

It is an arithmetic number, because the mean of its divisors is an integer number (2992899).

Almost surely, 2^65144500 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65144500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71829576).

65144500 is an abundant number, since it is smaller than the sum of its proper divisors (78514652).

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

65144500 is a wasteful number, since it uses less digits than its factorization.

65144500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1285 (or 1273 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 65144500 is about 8071.2142828697. The cubic root of 65144500 is about 402.3703014338.

Adding to 65144500 its reverse (544156), we get a palindrome (65688656).

The spelling of 65144500 in words is "sixty-five million, one hundred forty-four thousand, five hundred".