221455545 has 32 divisors (see below), whose sum is σ = 383076480. Its totient is φ = 108864000.

The previous prime is 221455541. The next prime is 221455561. The reversal of 221455545 is 545554122.

221455545 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221455545 - 2² = 221455541 is a prime.

It is a super-2 number, since 2×221455545² = 98085116822494050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221455541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45 + ... + 21045.

It is an arithmetic number, because the mean of its divisors is an integer number (11971140).

Almost surely, 2^221455545 is an apocalyptic number.

It is an amenable number.

221455545 is a deficient number, since it is larger than the sum of its proper divisors (161620935).

221455545 is a wasteful number, since it uses less digits than its factorization.

221455545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21065.

The product of its digits is 40000, while the sum is 33.

The square root of 221455545 is about 14881.3824962602. The cubic root of 221455545 is about 605.0094891848.

The spelling of 221455545 in words is "two hundred twenty-one million, four hundred fifty-five thousand, five hundred forty-five".