155607889 has 4 divisors (see below), whose sum is σ = 158158900. Its totient is φ = 153056880.

The previous prime is 155607887. The next prime is 155607899. The reversal of 155607889 is 988706551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 988706551 = 7 ⋅141243793.

It can be written as a sum of positive squares in 2 ways, for example, as 23357889 + 132250000 = 4833^2 + 11500^2 .

It is a cyclic number.

It is not a de Polignac number, because 155607889 - 2¹ = 155607887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155607887) 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, 1275414 + ... + 1275535.

It is an arithmetic number, because the mean of its divisors is an integer number (39539725).

Almost surely, 2^155607889 is an apocalyptic number.

It is an amenable number.

155607889 is a deficient number, since it is larger than the sum of its proper divisors (2551011).

155607889 is an equidigital number, since it uses as much as digits as its factorization.

155607889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2551010.

The product of its (nonzero) digits is 604800, while the sum is 49.

The square root of 155607889 is about 12474.2891180219. The cubic root of 155607889 is about 537.8698535400.

The spelling of 155607889 in words is "one hundred fifty-five million, six hundred seven thousand, eight hundred eighty-nine".