221415064242521 has 8 divisors (see below), whose sum is σ = 225958335371784. Its totient is φ = 216885334906240.

The previous prime is 221415064242467. The next prime is 221415064242529. The reversal of 221415064242521 is 125242460514122.

It can be written as a sum of positive squares in 4 ways, for example, as 53929121886025 + 167485942356496 = 7343645^2 + 12941636^2 .

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 221415064242521 - 2¹⁸ = 221415063980377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221415064242529) 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, 3385415210 + ... + 3385480611.

It is an arithmetic number, because the mean of its divisors is an integer number (28244791921473).

Almost surely, 2^{221415064242521} is an apocalyptic number.

It is an amenable number.

221415064242521 is a deficient number, since it is larger than the sum of its proper divisors (4543271129263).

221415064242521 is an equidigital number, since it uses as much as digits as its factorization.

221415064242521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6770896491.

The product of its (nonzero) digits is 307200, while the sum is 41.

The spelling of 221415064242521 in words is "two hundred twenty-one trillion, four hundred fifteen billion, sixty-four million, two hundred forty-two thousand, five hundred twenty-one".