2121154004 has 6 divisors (see below), whose sum is σ = 3712019514. Its totient is φ = 1060577000.

The previous prime is 2121154003. The next prime is 2121154027. The reversal of 2121154004 is 4004511212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1285365904 + 835788100 = 35852^2 + 28910^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121154003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265144247 + ... + 265144254.

It is an arithmetic number, because the mean of its divisors is an integer number (618669919).

Almost surely, 2^2121154004 is an apocalyptic number.

It is an amenable number.

2121154004 is a deficient number, since it is larger than the sum of its proper divisors (1590865510).

2121154004 is a wasteful number, since it uses less digits than its factorization.

2121154004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530288505 (or 530288503 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 2121154004 is about 46055.9877106115. The cubic root of 2121154004 is about 1284.8647082098.

Adding to 2121154004 its reverse (4004511212), we get a palindrome (6125665216).

The spelling of 2121154004 in words is "two billion, one hundred twenty-one million, one hundred fifty-four thousand, four".