155120621 has 8 divisors (see below), whose sum is σ = 162751488. Its totient is φ = 147654000.

The previous prime is 155120593. The next prime is 155120627. The reversal of 155120621 is 126021551.

It is a happy number.

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 155120621 - 2¹⁰ = 155119597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155120627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39125 + ... + 42906.

It is an arithmetic number, because the mean of its divisors is an integer number (20343936).

Almost surely, 2^155120621 is an apocalyptic number.

It is an amenable number.

155120621 is a deficient number, since it is larger than the sum of its proper divisors (7630867).

155120621 is an equidigital number, since it uses as much as digits as its factorization.

155120621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82123.

The product of its (nonzero) digits is 600, while the sum is 23.

The square root of 155120621 is about 12454.7429118388. The cubic root of 155120621 is about 537.3078408830.

The spelling of 155120621 in words is "one hundred fifty-five million, one hundred twenty thousand, six hundred twenty-one".