55566619 has 4 divisors (see below), whose sum is σ = 55584144. Its totient is φ = 55549096.

The previous prime is 55566617. The next prime is 55566629. The reversal of 55566619 is 91666555.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91666555 = 5 ⋅18333311.

It is a cyclic number.

It is not a de Polignac number, because 55566619 - 2¹ = 55566617 is a prime.

It is a super-2 number, since 2×55566619² = 6175298294182322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55566617) 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, 2527 + ... + 10840.

It is an arithmetic number, because the mean of its divisors is an integer number (13896036).

Almost surely, 2^55566619 is an apocalyptic number.

55566619 is a deficient number, since it is larger than the sum of its proper divisors (17525).

55566619 is a wasteful number, since it uses less digits than its factorization.

55566619 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17524.

The product of its digits is 243000, while the sum is 43.

The square root of 55566619 is about 7454.3020464695. The cubic root of 55566619 is about 381.5967414681.

The spelling of 55566619 in words is "fifty-five million, five hundred sixty-six thousand, six hundred nineteen".