201553621 has 8 divisors (see below), whose sum is σ = 205455744. Its totient is φ = 197677920.

The previous prime is 201553619. The next prime is 201553633. The reversal of 201553621 is 126355102.

201553621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 201553621 - 2¹ = 201553619 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 (201553721) 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, 9156 + ... + 22066.

It is an arithmetic number, because the mean of its divisors is an integer number (25681968).

Almost surely, 2^201553621 is an apocalyptic number.

It is an amenable number.

201553621 is a deficient number, since it is larger than the sum of its proper divisors (3902123).

201553621 is a wasteful number, since it uses less digits than its factorization.

201553621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13211.

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

The square root of 201553621 is about 14196.9581601130. The cubic root of 201553621 is about 586.3139152571.

The spelling of 201553621 in words is "two hundred one million, five hundred fifty-three thousand, six hundred twenty-one".