66531740 has 24 divisors (see below), whose sum is σ = 152418672. Its totient is φ = 24193280.

The previous prime is 66531719. The next prime is 66531779. The reversal of 66531740 is 4713566.

It is a junction number, because it is equal to n+sod(n) for n = 66531697 and 66531706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150989 + ... + 151428.

It is an arithmetic number, because the mean of its divisors is an integer number (6350778).

Almost surely, 2^66531740 is an apocalyptic number.

It is an amenable number.

66531740 is an abundant number, since it is smaller than the sum of its proper divisors (85886932).

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

66531740 is a wasteful number, since it uses less digits than its factorization.

66531740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302437 (or 302435 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 66531740 is about 8156.6990872534. The cubic root of 66531740 is about 405.2063978705.

The spelling of 66531740 in words is "sixty-six million, five hundred thirty-one thousand, seven hundred forty".