1255121550 has 72 divisors (see below), whose sum is σ = 3379174344. Its totient is φ = 333996480.

The previous prime is 1255121531. The next prime is 1255121587. The reversal of 1255121550 is 551215521.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 232684 + ... + 238016.

It is an arithmetic number, because the mean of its divisors is an integer number (46932977).

Almost surely, 2^1255121550 is an apocalyptic number.

1255121550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1255121550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1689587172).

1255121550 is an abundant number, since it is smaller than the sum of its proper divisors (2124052794).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1255121550 is a wasteful number, since it uses less digits than its factorization.

1255121550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5874 (or 5866 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 27.

The square root of 1255121550 is about 35427.6946752114. The cubic root of 1255121550 is about 1078.6865462807.

The spelling of 1255121550 in words is "one billion, two hundred fifty-five million, one hundred twenty-one thousand, five hundred fifty".