81301851 has 6 divisors (see below), whose sum is σ = 117436020. Its totient is φ = 54201228.

The previous prime is 81301807. The next prime is 81301859. The reversal of 81301851 is 15810318.

It is not a de Polignac number, because 81301851 - 2⁷ = 81301723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81301859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4516761 + ... + 4516778.

It is an arithmetic number, because the mean of its divisors is an integer number (19572670).

Almost surely, 2^81301851 is an apocalyptic number.

81301851 is a deficient number, since it is larger than the sum of its proper divisors (36134169).

81301851 is a wasteful number, since it uses less digits than its factorization.

81301851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9033545 (or 9033542 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 27.

The square root of 81301851 is about 9016.7539059242. The cubic root of 81301851 is about 433.2116671581.

The spelling of 81301851 in words is "eighty-one million, three hundred one thousand, eight hundred fifty-one".