2155021258 has 32 divisors (see below), whose sum is σ = 3556964880. Its totient is φ = 973209600.

The previous prime is 2155021243. The next prime is 2155021259. The reversal of 2155021258 is 8521205512.

It can be written as a sum of positive squares in 8 ways, for example, as 577104529 + 1577916729 = 24023^2 + 39723^2 .

It is not an unprimeable number, because it can be changed into a prime (2155021259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 219658 + ... + 229258.

Almost surely, 2^2155021258 is an apocalyptic number.

2155021258 is a deficient number, since it is larger than the sum of its proper divisors (1401943622).

2155021258 is a wasteful number, since it uses less digits than its factorization.

2155021258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9802.

The product of its (nonzero) digits is 8000, while the sum is 31.

The square root of 2155021258 is about 46422.2065180017. The cubic root of 2155021258 is about 1291.6668671319. Note that the first 3 decimals are identical.

The spelling of 2155021258 in words is "two billion, one hundred fifty-five million, twenty-one thousand, two hundred fifty-eight".