221665370501125 has 64 divisors (see below), whose sum is σ = 279851046261696. Its totient is φ = 175279104000000.

The previous prime is 221665370501087. The next prime is 221665370501143. The reversal of 221665370501125 is 521105073566122.

221665370501125 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 32 ways, for example, as 218659450231044 + 3005920270081 = 14787138^2 + 1733759^2 .

It is not a de Polignac number, because 221665370501125 - 2²³ = 221665362112517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22488112197 + ... + 22488122053.

It is an arithmetic number, because the mean of its divisors is an integer number (4372672597839).

Almost surely, 2^{221665370501125} is an apocalyptic number.

221665370501125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221665370501125 is a deficient number, since it is larger than the sum of its proper divisors (58185675760571).

221665370501125 is a wasteful number, since it uses less digits than its factorization.

221665370501125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12811 (or 12801 counting only the distinct ones).

The product of its (nonzero) digits is 756000, while the sum is 46.

The spelling of 221665370501125 in words is "two hundred twenty-one trillion, six hundred sixty-five billion, three hundred seventy million, five hundred one thousand, one hundred twenty-five".