2121478 has 4 divisors (see below), whose sum is σ = 3182220. Its totient is φ = 1060738.

The previous prime is 2121461. The next prime is 2121479. The reversal of 2121478 is 8741212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 530368 + ... + 530371.

It is an arithmetic number, because the mean of its divisors is an integer number (795555).

2^2121478 is an apocalyptic number.

2121478 is a deficient number, since it is larger than the sum of its proper divisors (1060742).

2121478 is a wasteful number, since it uses less digits than its factorization.

2121478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060741.

The product of its digits is 896, while the sum is 25.

The square root of 2121478 is about 1456.5294367091. The cubic root of 2121478 is about 128.4930123833.

The spelling of 2121478 in words is "two million, one hundred twenty-one thousand, four hundred seventy-eight".