609944921 has 4 divisors (see below), whose sum is σ = 645824052. Its totient is φ = 574065792.

The previous prime is 609944903. The next prime is 609944957. The reversal of 609944921 is 129449906.

609944921 = 4219² + 4220² + ... + 4252².

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 514609225 + 95335696 = 22685^2 + 9764^2 .

It is not a de Polignac number, because 609944921 - 2¹⁰ = 609943897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (609944021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17939540 + ... + 17939573.

It is an arithmetic number, because the mean of its divisors is an integer number (161456013).

Almost surely, 2^609944921 is an apocalyptic number.

It is an amenable number.

609944921 is a deficient number, since it is larger than the sum of its proper divisors (35879131).

609944921 is a wasteful number, since it uses less digits than its factorization.

609944921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35879130.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 609944921 is about 24697.0630035233. The cubic root of 609944921 is about 848.0670823467.

The spelling of 609944921 in words is "six hundred nine million, nine hundred forty-four thousand, nine hundred twenty-one".