55201621 has 8 divisors (see below), whose sum is σ = 57081024. Its totient is φ = 53347680.

The previous prime is 55201613. The next prime is 55201681. The reversal of 55201621 is 12610255.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 55201621 - 2³ = 55201613 is a prime.

It is a super-2 number, since 2×55201621² = 6094437922055282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 55201592 and 55201601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55201681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1905 + ... + 10678.

It is an arithmetic number, because the mean of its divisors is an integer number (7135128).

Almost surely, 2^55201621 is an apocalyptic number.

It is an amenable number.

55201621 is a deficient number, since it is larger than the sum of its proper divisors (1879403).

55201621 is a wasteful number, since it uses less digits than its factorization.

55201621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12731.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 55201621 is about 7429.7793372347. The cubic root of 55201621 is about 380.7593794390.

Adding to 55201621 its reverse (12610255), we get a palindrome (67811876).

The spelling of 55201621 in words is "fifty-five million, two hundred one thousand, six hundred twenty-one".