66993740 has 24 divisors (see below), whose sum is σ = 153477072. Its totient is φ = 24361280.

The previous prime is 66993737. The next prime is 66993763. The reversal of 66993740 is 4739966.

It is a super-2 number, since 2×66993740² = 8976322398375200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 66993691 and 66993700.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152039 + ... + 152478.

It is an arithmetic number, because the mean of its divisors is an integer number (6394878).

Almost surely, 2^66993740 is an apocalyptic number.

It is an amenable number.

66993740 is an abundant number, since it is smaller than the sum of its proper divisors (86483332).

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

66993740 is a wasteful number, since it uses less digits than its factorization.

66993740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304537 (or 304535 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 44.

The square root of 66993740 is about 8184.9703725792. The cubic root of 66993740 is about 406.1421602520.

The spelling of 66993740 in words is "sixty-six million, nine hundred ninety-three thousand, seven hundred forty".