421111666 has 4 divisors (see below), whose sum is σ = 631667502. Its totient is φ = 210555832.

The previous prime is 421111601. The next prime is 421111673. The reversal of 421111666 is 666111124.

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

It can be written as a sum of positive squares in only one way, i.e., 421111441 + 225 = 20521^2 + 15^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105277915 + ... + 105277918.

Almost surely, 2^421111666 is an apocalyptic number.

421111666 is a deficient number, since it is larger than the sum of its proper divisors (210555836).

421111666 is a wasteful number, since it uses less digits than its factorization.

421111666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210555835.

The product of its digits is 1728, while the sum is 28.

The square root of 421111666 is about 20521.0054821882. The cubic root of 421111666 is about 749.5473808287.

The spelling of 421111666 in words is "four hundred twenty-one million, one hundred eleven thousand, six hundred sixty-six".