428344621 has 4 divisors (see below), whose sum is σ = 429493372. Its totient is φ = 427195872.

The previous prime is 428344583. The next prime is 428344667. The reversal of 428344621 is 126443824.

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

It can be written as a sum of positive squares in 2 ways, for example, as 320911396 + 107433225 = 17914^2 + 10365^2 .

It is a cyclic number.

It is not a de Polignac number, because 428344621 - 2⁹ = 428344109 is a prime.

It is a super-2 number, since 2×428344621² = 366958228679267282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (428344691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 573816 + ... + 574561.

It is an arithmetic number, because the mean of its divisors is an integer number (107373343).

Almost surely, 2^428344621 is an apocalyptic number.

It is an amenable number.

428344621 is a deficient number, since it is larger than the sum of its proper divisors (1148751).

428344621 is a wasteful number, since it uses less digits than its factorization.

428344621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1148750.

The product of its digits is 36864, while the sum is 34.

The square root of 428344621 is about 20696.4881320479. The cubic root of 428344621 is about 753.8144168916.

The spelling of 428344621 in words is "four hundred twenty-eight million, three hundred forty-four thousand, six hundred twenty-one".