1002555544221 has 120 divisors (see below), whose sum is σ = 1907784356544. Its totient is φ = 518821873920.

The previous prime is 1002555544213. The next prime is 1002555544223. The reversal of 1002555544221 is 1224455552001.

1002555544221 is a `hidden beast` number, since 10 + 0 + 2 + 55 + 554 + 42 + 2 + 1 = 666.

It is not a de Polignac number, because 1002555544221 - 2³ = 1002555544213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002555544223) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 11438661 + ... + 11525973.

Almost surely, 2^{1002555544221} is an apocalyptic number.

1002555544221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1002555544221 is a deficient number, since it is larger than the sum of its proper divisors (905228812323).

1002555544221 is a wasteful number, since it uses less digits than its factorization.

1002555544221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87613 (or 87597 counting only the distinct ones).

The product of its (nonzero) digits is 80000, while the sum is 36.

The spelling of 1002555544221 in words is "one trillion, two billion, five hundred fifty-five million, five hundred forty-four thousand, two hundred twenty-one".