2521629978 has 32 divisors (see below), whose sum is σ = 6014324736. Its totient is φ = 689140848.

The previous prime is 2521629977. The next prime is 2521629989. The reversal of 2521629978 is 8799261252.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2521629978.

It is not an unprimeable number, because it can be changed into a prime (2521629977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1304226 + ... + 1306157.

It is an arithmetic number, because the mean of its divisors is an integer number (187947648).

Almost surely, 2^2521629978 is an apocalyptic number.

2521629978 is an abundant number, since it is smaller than the sum of its proper divisors (3492694758).

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

2521629978 is a wasteful number, since it uses less digits than its factorization.

2521629978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2610418.

The product of its digits is 1088640, while the sum is 51.

The square root of 2521629978 is about 50215.8339371159. The cubic root of 2521629978 is about 1361.1117599669. Note that the first 3 decimals are identical.

The spelling of 2521629978 in words is "two billion, five hundred twenty-one million, six hundred twenty-nine thousand, nine hundred seventy-eight".