155510240221 has 8 divisors (see below), whose sum is σ = 177732111104. Its totient is φ = 133289899920.

The previous prime is 155510240201. The next prime is 155510240243. The reversal of 155510240221 is 122042015551.

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 155510240221 - 2¹⁵ = 155510207453 is a prime.

It is a super-2 number, since 2×155510240221² (a number of 23 digits) contains 22 as substring.

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 155510240221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155510240201) 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, 155970 + ... + 579091.

It is an arithmetic number, because the mean of its divisors is an integer number (22216513888).

Almost surely, 2^155510240221 is an apocalyptic number.

It is an amenable number.

155510240221 is a deficient number, since it is larger than the sum of its proper divisors (22221870883).

155510240221 is an equidigital number, since it uses as much as digits as its factorization.

155510240221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765291.

The product of its (nonzero) digits is 4000, while the sum is 28.

Adding to 155510240221 its reverse (122042015551), we get a palindrome (277552255772).

The spelling of 155510240221 in words is "one hundred fifty-five billion, five hundred ten million, two hundred forty thousand, two hundred twenty-one".