155011421 has 4 divisors (see below), whose sum is σ = 161751072. Its totient is φ = 148271772.

The previous prime is 155011403. The next prime is 155011453. The reversal of 155011421 is 124110551.

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.

It is a cyclic number.

It is not a de Polignac number, because 155011421 - 2¹⁴ = 154995037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 155011393 and 155011402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155011921) 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, 3369791 + ... + 3369836.

It is an arithmetic number, because the mean of its divisors is an integer number (40437768).

Almost surely, 2^155011421 is an apocalyptic number.

It is an amenable number.

155011421 is a deficient number, since it is larger than the sum of its proper divisors (6739651).

155011421 is an equidigital number, since it uses as much as digits as its factorization.

155011421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6739650.

The product of its (nonzero) digits is 200, while the sum is 20.

The square root of 155011421 is about 12450.3582679375. The cubic root of 155011421 is about 537.1817287228.

Adding to 155011421 its reverse (124110551), we get a palindrome (279121972).

The spelling of 155011421 in words is "one hundred fifty-five million, eleven thousand, four hundred twenty-one".