669172619 has 4 divisors (see below), whose sum is σ = 672120744. Its totient is φ = 666224496.

The previous prime is 669172597. The next prime is 669172661. The reversal of 669172619 is 916271966.

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 669172619 - 2¹² = 669168523 is a prime.

It is a super-2 number, since 2×669172619² = 895583988038638322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669172519) 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, 1473722 + ... + 1474175.

It is an arithmetic number, because the mean of its divisors is an integer number (168030186).

Almost surely, 2^669172619 is an apocalyptic number.

669172619 is a deficient number, since it is larger than the sum of its proper divisors (2948125).

669172619 is a wasteful number, since it uses less digits than its factorization.

669172619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2948124.

The product of its digits is 244944, while the sum is 47.

The square root of 669172619 is about 25868.3710155858. The cubic root of 669172619 is about 874.6736716182.

The spelling of 669172619 in words is "six hundred sixty-nine million, one hundred seventy-two thousand, six hundred nineteen".