42131779 has 2 divisors, whose sum is σ = 42131780. Its totient is φ = 42131778.

The previous prime is 42131777. The next prime is 42131807. The reversal of 42131779 is 97713124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42131779 - 2¹ = 42131777 is a prime.

Together with 42131777, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (42131777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21065889 + 21065890.

It is an arithmetic number, because the mean of its divisors is an integer number (21065890).

Almost surely, 2^42131779 is an apocalyptic number.

42131779 is a deficient number, since it is larger than the sum of its proper divisors (1).

42131779 is an equidigital number, since it uses as much as digits as its factorization.

42131779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 34.

The square root of 42131779 is about 6490.8997065122. The cubic root of 42131779 is about 347.9658304188.

The spelling of 42131779 in words is "forty-two million, one hundred thirty-one thousand, seven hundred seventy-nine".