221461551 has 12 divisors (see below), whose sum is σ = 330208320. Its totient is φ = 142878240.

The previous prime is 221461543. The next prime is 221461553. The reversal of 221461551 is 155164122.

It is not a de Polignac number, because 221461551 - 2³ = 221461543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221461553) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 396606 + ... + 397163.

It is an arithmetic number, because the mean of its divisors is an integer number (27517360).

Almost surely, 2^221461551 is an apocalyptic number.

221461551 is a deficient number, since it is larger than the sum of its proper divisors (108746769).

221461551 is a wasteful number, since it uses less digits than its factorization.

221461551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793806 (or 793803 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 221461551 is about 14881.5842906594. The cubic root of 221461551 is about 605.0149585355.

The spelling of 221461551 in words is "two hundred twenty-one million, four hundred sixty-one thousand, five hundred fifty-one".