47151781 has 2 divisors, whose sum is σ = 47151782. Its totient is φ = 47151780.

The previous prime is 47151773. The next prime is 47151791. The reversal of 47151781 is 18715174.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33535681 + 13616100 = 5791^2 + 3690^2 .

It is a cyclic number.

It is not a de Polignac number, because 47151781 - 2³ = 47151773 is a prime.

It is a super-2 number, since 2×47151781² = 4446580902943922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (47151751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23575890 + 23575891.

It is an arithmetic number, because the mean of its divisors is an integer number (23575891).

Almost surely, 2^47151781 is an apocalyptic number.

47151781 is the 3965-th hex number.

It is an amenable number.

47151781 is a deficient number, since it is larger than the sum of its proper divisors (1).

47151781 is an equidigital number, since it uses as much as digits as its factorization.

47151781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7840, while the sum is 34.

The square root of 47151781 is about 6866.7154448106. The cubic root of 47151781 is about 361.2706666337.

The spelling of 47151781 in words is "forty-seven million, one hundred fifty-one thousand, seven hundred eighty-one".