155121793 has 4 divisors (see below), whose sum is σ = 157085440. Its totient is φ = 153158148.

The previous prime is 155121781. The next prime is 155121803. The reversal of 155121793 is 397121551.

155121793 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 an emirpimes, since its reverse is a distinct semiprime: 397121551 = 83 ⋅4784597.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155121793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155121713) 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, 981705 + ... + 981862.

It is an arithmetic number, because the mean of its divisors is an integer number (39271360).

Almost surely, 2^155121793 is an apocalyptic number.

It is an amenable number.

155121793 is a deficient number, since it is larger than the sum of its proper divisors (1963647).

155121793 is an equidigital number, since it uses as much as digits as its factorization.

155121793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1963646.

The product of its digits is 9450, while the sum is 34.

The square root of 155121793 is about 12454.7899620989. The cubic root of 155121793 is about 537.3091940734.

The spelling of 155121793 in words is "one hundred fifty-five million, one hundred twenty-one thousand, seven hundred ninety-three".