66901019 has 4 divisors (see below), whose sum is σ = 67044744. Its totient is φ = 66757296.

The previous prime is 66901013. The next prime is 66901031. The reversal of 66901019 is 91010966.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66901019 - 2²⁰ = 65852443 is a prime.

It is a super-2 number, since 2×66901019² = 8951492686476722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66901013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71162 + ... + 72095.

It is an arithmetic number, because the mean of its divisors is an integer number (16761186).

Almost surely, 2^66901019 is an apocalyptic number.

66901019 is a deficient number, since it is larger than the sum of its proper divisors (143725).

66901019 is a wasteful number, since it uses less digits than its factorization.

66901019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143724.

The product of its (nonzero) digits is 2916, while the sum is 32.

The square root of 66901019 is about 8179.3043102699. The cubic root of 66901019 is about 405.9547034649.

The spelling of 66901019 in words is "sixty-six million, nine hundred one thousand, nineteen".