2021187155 has 16 divisors (see below), whose sum is σ = 2613765504. Its totient is φ = 1491557760.

The previous prime is 2021187151. The next prime is 2021187221. The reversal of 2021187155 is 5517811202.

It is not a de Polignac number, because 2021187155 - 2² = 2021187151 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021187151) 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, 94070 + ... + 113540.

It is an arithmetic number, because the mean of its divisors is an integer number (163360344).

Almost surely, 2^2021187155 is an apocalyptic number.

2021187155 is a deficient number, since it is larger than the sum of its proper divisors (592578349).

2021187155 is a wasteful number, since it uses less digits than its factorization.

2021187155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21086.

The product of its (nonzero) digits is 5600, while the sum is 32.

The square root of 2021187155 is about 44957.6150946644. The cubic root of 2021187155 is about 1264.3544551101.

Adding to 2021187155 its reverse (5517811202), we get a palindrome (7538998357).

The spelling of 2021187155 in words is "two billion, twenty-one million, one hundred eighty-seven thousand, one hundred fifty-five".