42520381 has 2 divisors, whose sum is σ = 42520382. Its totient is φ = 42520380.

The previous prime is 42520369. The next prime is 42520391. The reversal of 42520381 is 18302524.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33120025 + 9400356 = 5755^2 + 3066^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42520381 is a prime.

It is a super-2 number, since 2×42520381² = 3615965600770322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42520391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21260190 + 21260191.

It is an arithmetic number, because the mean of its divisors is an integer number (21260191).

Almost surely, 2^42520381 is an apocalyptic number.

It is an amenable number.

42520381 is a deficient number, since it is larger than the sum of its proper divisors (1).

42520381 is an equidigital number, since it uses as much as digits as its factorization.

42520381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 42520381 is about 6520.7653691879. The cubic root of 42520381 is about 349.0323776827.

The spelling of 42520381 in words is "forty-two million, five hundred twenty thousand, three hundred eighty-one".