155013434021 has 4 divisors (see below), whose sum is σ = 155015515200. Its totient is φ = 155011352844.

The previous prime is 155013434003. The next prime is 155013434039. The reversal of 155013434021 is 120434310551.

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: 120434310551 = 383 ⋅314449897.

It is an interprime number because it is at equal distance from previous prime (155013434003) and next prime (155013434039).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155013434021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155013434221) 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, 924551 + ... + 1079268.

It is an arithmetic number, because the mean of its divisors is an integer number (38753878800).

Almost surely, 2^155013434021 is an apocalyptic number.

It is an amenable number.

155013434021 is a deficient number, since it is larger than the sum of its proper divisors (2081179).

155013434021 is an equidigital number, since it uses as much as digits as its factorization.

155013434021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2081178.

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 155013434021 its reverse (120434310551), we get a palindrome (275447744572).

The spelling of 155013434021 in words is "one hundred fifty-five billion, thirteen million, four hundred thirty-four thousand, twenty-one".