42613721 has 2 divisors, whose sum is σ = 42613722. Its totient is φ = 42613720.

The previous prime is 42613709. The next prime is 42613741. The reversal of 42613721 is 12731624.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28090000 + 14523721 = 5300^2 + 3811^2 .

It is a cyclic number.

It is not a de Polignac number, because 42613721 - 2¹⁸ = 42351577 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42613741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21306860 + 21306861.

It is an arithmetic number, because the mean of its divisors is an integer number (21306861).

Almost surely, 2^42613721 is an apocalyptic number.

It is an amenable number.

42613721 is a deficient number, since it is larger than the sum of its proper divisors (1).

42613721 is an equidigital number, since it uses as much as digits as its factorization.

42613721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 26.

The square root of 42613721 is about 6527.9185809874. The cubic root of 42613721 is about 349.2875876289.

It can be divided in two parts, 42613 and 721, that added together give a palindrome (43334).

The spelling of 42613721 in words is "forty-two million, six hundred thirteen thousand, seven hundred twenty-one".