55006621 has 4 divisors (see below), whose sum is σ = 55439872. Its totient is φ = 54573372.

The previous prime is 55006619. The next prime is 55006631. The reversal of 55006621 is 12660055.

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 55006621 - 2¹ = 55006619 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 (55006631) 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, 216435 + ... + 216688.

It is an arithmetic number, because the mean of its divisors is an integer number (13859968).

Almost surely, 2^55006621 is an apocalyptic number.

It is an amenable number.

55006621 is a deficient number, since it is larger than the sum of its proper divisors (433251).

55006621 is a wasteful number, since it uses less digits than its factorization.

55006621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433250.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 55006621 is about 7416.6448613912. The cubic root of 55006621 is about 380.3105056749.

Adding to 55006621 its reverse (12660055), we get a palindrome (67666676).

It can be divided in two parts, 5500 and 6621, that added together give a palindrome (12121).

The spelling of 55006621 in words is "fifty-five million, six thousand, six hundred twenty-one".