42717421 has 2 divisors, whose sum is σ = 42717422. Its totient is φ = 42717420.

The previous prime is 42717403. The next prime is 42717461. The reversal of 42717421 is 12471724.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41538025 + 1179396 = 6445^2 + 1086^2 .

It is a cyclic number.

It is not a de Polignac number, because 42717421 - 2²¹ = 40620269 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42717421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42717461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21358710 + 21358711.

It is an arithmetic number, because the mean of its divisors is an integer number (21358711).

Almost surely, 2^42717421 is an apocalyptic number.

It is an amenable number.

42717421 is a deficient number, since it is larger than the sum of its proper divisors (1).

42717421 is an equidigital number, since it uses as much as digits as its factorization.

42717421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3136, while the sum is 28.

The square root of 42717421 is about 6535.8565620736. The cubic root of 42717421 is about 349.5706872223.

The spelling of 42717421 in words is "forty-two million, seven hundred seventeen thousand, four hundred twenty-one".