42639461 has 2 divisors, whose sum is σ = 42639462. Its totient is φ = 42639460.

The previous prime is 42639449. The next prime is 42639463. The reversal of 42639461 is 16493624.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30459361 + 12180100 = 5519^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 42639461 - 2⁶ = 42639397 is a prime.

Together with 42639463, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42639463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21319730 + 21319731.

It is an arithmetic number, because the mean of its divisors is an integer number (21319731).

Almost surely, 2^42639461 is an apocalyptic number.

It is an amenable number.

42639461 is a deficient number, since it is larger than the sum of its proper divisors (1).

42639461 is an equidigital number, since it uses as much as digits as its factorization.

42639461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 35.

The square root of 42639461 is about 6529.8898153032. The cubic root of 42639461 is about 349.3579002941.

The spelling of 42639461 in words is "forty-two million, six hundred thirty-nine thousand, four hundred sixty-one".