1255021551 has 24 divisors (see below), whose sum is σ = 2085517824. Its totient is φ = 712400400.

The previous prime is 1255021451. The next prime is 1255021561. The reversal of 1255021551 is 1551205521.

1255021551 is a `hidden beast` number, since 1 + 2 + 5 + 502 + 155 + 1 = 666.

It is not a de Polignac number, because 1255021551 - 2⁷ = 1255021423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1255021561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56451 + ... + 75476.

It is an arithmetic number, because the mean of its divisors is an integer number (86896576).

Almost surely, 2^1255021551 is an apocalyptic number.

1255021551 is a deficient number, since it is larger than the sum of its proper divisors (830496273).

1255021551 is a wasteful number, since it uses less digits than its factorization.

1255021551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132091 (or 132088 counting only the distinct ones).

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

The square root of 1255021551 is about 35426.2833359640. The cubic root of 1255021551 is about 1078.6578982078.

The spelling of 1255021551 in words is "one billion, two hundred fifty-five million, twenty-one thousand, five hundred fifty-one".