2521216401 has 16 divisors (see below), whose sum is σ = 3668172480. Its totient is φ = 1527614720.

The previous prime is 2521216363. The next prime is 2521216429. The reversal of 2521216401 is 1046121252.

It is a cyclic number.

It is not a de Polignac number, because 2521216401 - 2⁷ = 2521216273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2521214401) 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, 166765 + ... + 181253.

It is an arithmetic number, because the mean of its divisors is an integer number (229260780).

Almost surely, 2^2521216401 is an apocalyptic number.

It is an amenable number.

2521216401 is a deficient number, since it is larger than the sum of its proper divisors (1146956079).

2521216401 is a wasteful number, since it uses less digits than its factorization.

2521216401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19776.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 2521216401 is about 50211.7157743091. The cubic root of 2521216401 is about 1361.0373431146.

Adding to 2521216401 its reverse (1046121252), we get a palindrome (3567337653).

The spelling of 2521216401 in words is "two billion, five hundred twenty-one million, two hundred sixteen thousand, four hundred one".