2011221870 has 64 divisors (see below), whose sum is σ = 5525245440. Its totient is φ = 458978688.

The previous prime is 2011221857. The next prime is 2011221871. The reversal of 2011221870 is 781221102.

It is a self number, because there is not a number n which added to its sum of digits gives 2011221870.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011221871) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 131124 + ... + 145656.

It is an arithmetic number, because the mean of its divisors is an integer number (86331960).

Almost surely, 2^2011221870 is an apocalyptic number.

2011221870 is an abundant number, since it is smaller than the sum of its proper divisors (3514023570).

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

2011221870 is a wasteful number, since it uses less digits than its factorization.

2011221870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15209.

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 2011221870 is about 44846.6483697500. The cubic root of 2011221870 is about 1262.2731013341.

Adding to 2011221870 its reverse (781221102), we get a palindrome (2792442972).

The spelling of 2011221870 in words is "two billion, eleven million, two hundred twenty-one thousand, eight hundred seventy".