65451540 has 192 divisors, whose sum is σ = 236371968. Its totient is φ = 13132800.

The previous prime is 65451527. The next prime is 65451541. The reversal of 65451540 is 4515456.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 65451498 and 65451507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65451541) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 142992 + ... + 143448.

It is an arithmetic number, because the mean of its divisors is an integer number (1231104).

Almost surely, 2^65451540 is an apocalyptic number.

65451540 is a gapful number since it is divisible by the number (60) 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 65451540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118185984).

65451540 is an abundant number, since it is smaller than the sum of its proper divisors (170920428).

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

65451540 is a wasteful number, since it uses less digits than its factorization.

65451540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518 (or 516 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

The square root of 65451540 is about 8090.2126053646. The cubic root of 65451540 is about 403.0014633783.

Adding to 65451540 its reverse (4515456), we get a palindrome (69966996).

The spelling of 65451540 in words is "sixty-five million, four hundred fifty-one thousand, five hundred forty".