72143761 has 2 divisors, whose sum is σ = 72143762. Its totient is φ = 72143760.

The previous prime is 72143737. The next prime is 72143803. The reversal of 72143761 is 16734127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46580625 + 25563136 = 6825^2 + 5056^2 .

It is an emirp because it is prime and its reverse (16734127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72143761 - 2²¹ = 70046609 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72143861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36071880 + 36071881.

It is an arithmetic number, because the mean of its divisors is an integer number (36071881).

Almost surely, 2^72143761 is an apocalyptic number.

It is an amenable number.

72143761 is a deficient number, since it is larger than the sum of its proper divisors (1).

72143761 is an equidigital number, since it uses as much as digits as its factorization.

72143761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7056, while the sum is 31.

The square root of 72143761 is about 8493.7483480499. The cubic root of 72143761 is about 416.2934647263.

Adding to 72143761 its reverse (16734127), we get a palindrome (88877888).

The spelling of 72143761 in words is "seventy-two million, one hundred forty-three thousand, seven hundred sixty-one".