155021221533 has 8 divisors (see below), whose sum is σ = 207368236768. Its totient is φ = 103010843664.

The previous prime is 155021221513. The next prime is 155021221547. The reversal of 155021221533 is 335122120551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 155021221533 - 2¹⁶ = 155021155997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 155021221533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155021221513) 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, 84158266 + ... + 84160107.

It is an arithmetic number, because the mean of its divisors is an integer number (25921029596).

Almost surely, 2^155021221533 is an apocalyptic number.

It is an amenable number.

155021221533 is a deficient number, since it is larger than the sum of its proper divisors (52347015235).

155021221533 is a wasteful number, since it uses less digits than its factorization.

155021221533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168318683.

The product of its (nonzero) digits is 9000, while the sum is 30.

The spelling of 155021221533 in words is "one hundred fifty-five billion, twenty-one million, two hundred twenty-one thousand, five hundred thirty-three".