421386661 has 4 divisors (see below), whose sum is σ = 422560800. Its totient is φ = 420212524.

The previous prime is 421386649. The next prime is 421386677. The reversal of 421386661 is 166683124.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 421386661 - 2⁷ = 421386533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 421386661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421386961) 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, 586531 + ... + 587248.

It is an arithmetic number, because the mean of its divisors is an integer number (105640200).

Almost surely, 2^421386661 is an apocalyptic number.

It is an amenable number.

421386661 is a deficient number, since it is larger than the sum of its proper divisors (1174139).

421386661 is a wasteful number, since it uses less digits than its factorization.

421386661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1174138.

The product of its digits is 41472, while the sum is 37.

The square root of 421386661 is about 20527.7047182582. The cubic root of 421386661 is about 749.7105021950.

The spelling of 421386661 in words is "four hundred twenty-one million, three hundred eighty-six thousand, six hundred sixty-one".