221001215133550 has 96 divisors (see below), whose sum is σ = 412720051011840. Its totient is φ = 88044815980800.

The previous prime is 221001215133539. The next prime is 221001215133571. The reversal of 221001215133550 is 55331512100122.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48861641589 + ... + 48861646111.

It is an arithmetic number, because the mean of its divisors is an integer number (4299167198040).

Almost surely, 2^{221001215133550} is an apocalyptic number.

221001215133550 is a deficient number, since it is larger than the sum of its proper divisors (191718835878290).

221001215133550 is a wasteful number, since it uses less digits than its factorization.

221001215133550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8378 (or 8373 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 31.

Adding to 221001215133550 its reverse (55331512100122), we get a palindrome (276332727233672).

The spelling of 221001215133550 in words is "two hundred twenty-one trillion, one billion, two hundred fifteen million, one hundred thirty-three thousand, five hundred fifty".