42247861 has 2 divisors, whose sum is σ = 42247862. Its totient is φ = 42247860.

The previous prime is 42247859. The next prime is 42247883. The reversal of 42247861 is 16874224.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38825361 + 3422500 = 6231^2 + 1850^2 .

It is a cyclic number.

It is not a de Polignac number, because 42247861 - 2¹ = 42247859 is a prime.

Together with 42247859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42247061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21123930 + 21123931.

It is an arithmetic number, because the mean of its divisors is an integer number (21123931).

Almost surely, 2^42247861 is an apocalyptic number.

It is an amenable number.

42247861 is a deficient number, since it is larger than the sum of its proper divisors (1).

42247861 is an equidigital number, since it uses as much as digits as its factorization.

42247861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 34.

The square root of 42247861 is about 6499.8354594559. The cubic root of 42247861 is about 348.2851106269.

The spelling of 42247861 in words is "forty-two million, two hundred forty-seven thousand, eight hundred sixty-one".