66072540 has 96 divisors (see below), whose sum is σ = 197455104. Its totient is φ = 16450560.

The previous prime is 66072521. The next prime is 66072547. The reversal of 66072540 is 4527066.

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 = 66072498 and 66072507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66072547) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 215067 + ... + 215373.

It is an arithmetic number, because the mean of its divisors is an integer number (2056824).

Almost surely, 2^66072540 is an apocalyptic number.

66072540 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 66072540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98727552).

66072540 is an abundant number, since it is smaller than the sum of its proper divisors (131382564).

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

66072540 is a wasteful number, since it uses less digits than its factorization.

66072540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 547 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 30.

The square root of 66072540 is about 8128.5017069568. The cubic root of 66072540 is about 404.2720041918.

The spelling of 66072540 in words is "sixty-six million, seventy-two thousand, five hundred forty".