42521260421 has 12 divisors (see below), whose sum is σ = 45233570340. Its totient is φ = 39963371520.

The previous prime is 42521260363. The next prime is 42521260459. The reversal of 42521260421 is 12406212524.

It can be written as a sum of positive squares in 6 ways, for example, as 551592196 + 41969668225 = 23486^2 + 204865^2 .

It is a de Polignac number, because none of the positive numbers 2^k-42521260421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42521260921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 101141 + ... + 308661.

It is an arithmetic number, because the mean of its divisors is an integer number (3769464195).

Almost surely, 2^42521260421 is an apocalyptic number.

It is an amenable number.

42521260421 is a deficient number, since it is larger than the sum of its proper divisors (2712309919).

42521260421 is a wasteful number, since it uses less digits than its factorization.

42521260421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208264 (or 208247 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 29.

Adding to 42521260421 its reverse (12406212524), we get a palindrome (54927472945).

The spelling of 42521260421 in words is "forty-two billion, five hundred twenty-one million, two hundred sixty thousand, four hundred twenty-one".