42781951 has 2 divisors, whose sum is σ = 42781952. Its totient is φ = 42781950.

The previous prime is 42781943. The next prime is 42781961. The reversal of 42781951 is 15918724.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42781951 - 2³ = 42781943 is a prime.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 42781951.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42781961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21390975 + 21390976.

It is an arithmetic number, because the mean of its divisors is an integer number (21390976).

Almost surely, 2^42781951 is an apocalyptic number.

42781951 is a deficient number, since it is larger than the sum of its proper divisors (1).

42781951 is an equidigital number, since it uses as much as digits as its factorization.

42781951 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 37.

The square root of 42781951 is about 6540.7913129835. The cubic root of 42781951 is about 349.7466220568.

The spelling of 42781951 in words is "forty-two million, seven hundred eighty-one thousand, nine hundred fifty-one".