73563781 has 2 divisors, whose sum is σ = 73563782. Its totient is φ = 73563780.

The previous prime is 73563769. The next prime is 73563793. The reversal of 73563781 is 18736537.

It is a balanced prime because it is at equal distance from previous prime (73563769) and next prime (73563793).

It can be written as a sum of positive squares in only one way, i.e., 71673156 + 1890625 = 8466^2 + 1375^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73563781 is a prime.

It is a super-2 number, since 2×73563781² = 10823259750031922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73563761) 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 as a sum of consecutive naturals, namely, 36781890 + 36781891.

It is an arithmetic number, because the mean of its divisors is an integer number (36781891).

Almost surely, 2^73563781 is an apocalyptic number.

It is an amenable number.

73563781 is a deficient number, since it is larger than the sum of its proper divisors (1).

73563781 is an equidigital number, since it uses as much as digits as its factorization.

73563781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 105840, while the sum is 40.

The square root of 73563781 is about 8576.9330765723. The cubic root of 73563781 is about 419.0070667503.

It can be divided in two parts, 735 and 63781, that added together give a square (64516 = 254²).

The spelling of 73563781 in words is "seventy-three million, five hundred sixty-three thousand, seven hundred eighty-one".