66991467 has 8 divisors (see below), whose sum is σ = 89965120. Its totient is φ = 44339400.

The previous prime is 66991459. The next prime is 66991469. The reversal of 66991467 is 76419966.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66991467 - 2³ = 66991459 is a prime.

It is a super-3 number, since 3×66991467³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66991469) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79909 + ... + 80742.

It is an arithmetic number, because the mean of its divisors is an integer number (11245640).

Almost surely, 2^66991467 is an apocalyptic number.

66991467 is a deficient number, since it is larger than the sum of its proper divisors (22973653).

66991467 is a wasteful number, since it uses less digits than its factorization.

66991467 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160793.

The product of its digits is 489888, while the sum is 48.

The square root of 66991467 is about 8184.8315193411. The cubic root of 66991467 is about 406.1375669295.

The spelling of 66991467 in words is "sixty-six million, nine hundred ninety-one thousand, four hundred sixty-seven".