155120513 has 4 divisors (see below), whose sum is σ = 155145648. Its totient is φ = 155095380.

The previous prime is 155120509. The next prime is 155120519. The reversal of 155120513 is 315021551.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 315021551 = 13 ⋅24232427.

It is a cyclic number.

It is not a de Polignac number, because 155120513 - 2² = 155120509 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (155120519) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3770 + ... + 18012.

It is an arithmetic number, because the mean of its divisors is an integer number (38786412).

Almost surely, 2^155120513 is an apocalyptic number.

It is an amenable number.

155120513 is a deficient number, since it is larger than the sum of its proper divisors (25135).

155120513 is a wasteful number, since it uses less digits than its factorization.

155120513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25134.

The product of its (nonzero) digits is 750, while the sum is 23.

The square root of 155120513 is about 12454.7385761404. The cubic root of 155120513 is about 537.3077161860.

The spelling of 155120513 in words is "one hundred fifty-five million, one hundred twenty thousand, five hundred thirteen".