153121391 has 4 divisors (see below), whose sum is σ = 153238800. Its totient is φ = 153003984.

The previous prime is 153121333. The next prime is 153121393. The reversal of 153121391 is 193121351.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-153121391 is a prime.

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 153121391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (153121393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56726 + ... + 59363.

It is an arithmetic number, because the mean of its divisors is an integer number (38309700).

Almost surely, 2^153121391 is an apocalyptic number.

153121391 is a deficient number, since it is larger than the sum of its proper divisors (117409).

153121391 is a wasteful number, since it uses less digits than its factorization.

153121391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117408.

The product of its digits is 810, while the sum is 26.

The square root of 153121391 is about 12374.2228442840. Note that the first 3 decimals coincide. The cubic root of 153121391 is about 534.9895371640.

It can be divided in two parts, 1531 and 21391, that added together give a palindrome (22922).

The spelling of 153121391 in words is "one hundred fifty-three million, one hundred twenty-one thousand, three hundred ninety-one".