64198621 has 4 divisors (see below), whose sum is σ = 64250172. Its totient is φ = 64147072.

The previous prime is 64198619. The next prime is 64198633. The reversal of 64198621 is 12689146.

It is a happy number.

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 41024025 + 23174596 = 6405^2 + 4814^2 .

It is a cyclic number.

It is not a de Polignac number, because 64198621 - 2¹ = 64198619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64198021) 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, 23860 + ... + 26413.

It is an arithmetic number, because the mean of its divisors is an integer number (16062543).

Almost surely, 2^64198621 is an apocalyptic number.

It is an amenable number.

64198621 is a deficient number, since it is larger than the sum of its proper divisors (51551).

64198621 is a wasteful number, since it uses less digits than its factorization.

64198621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51550.

The product of its digits is 20736, while the sum is 37.

The square root of 64198621 is about 8012.4041959951. The cubic root of 64198621 is about 400.4133664233.

The spelling of 64198621 in words is "sixty-four million, one hundred ninety-eight thousand, six hundred twenty-one".