2405521421 has 2 divisors, whose sum is σ = 2405521422. Its totient is φ = 2405521420.

The previous prime is 2405521379. The next prime is 2405521427. The reversal of 2405521421 is 1241255042.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1759802500 + 645718921 = 41950^2 + 25411^2 .

It is a cyclic number.

It is not a de Polignac number, because 2405521421 - 2⁶ = 2405521357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2405521427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1202760710 + 1202760711.

It is an arithmetic number, because the mean of its divisors is an integer number (1202760711).

Almost surely, 2^2405521421 is an apocalyptic number.

It is an amenable number.

2405521421 is a deficient number, since it is larger than the sum of its proper divisors (1).

2405521421 is an equidigital number, since it uses as much as digits as its factorization.

2405521421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 2405521421 is about 49046.1152488146. The cubic root of 2405521421 is about 1339.8918419051.

Adding to 2405521421 its reverse (1241255042), we get a palindrome (3646776463).

The spelling of 2405521421 in words is "two billion, four hundred five million, five hundred twenty-one thousand, four hundred twenty-one".