72191101 has 2 divisors, whose sum is σ = 72191102. Its totient is φ = 72191100.

The previous prime is 72191057. The next prime is 72191113. The reversal of 72191101 is 10119127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62394201 + 9796900 = 7899^2 + 3130^2 .

It is a cyclic number.

It is not a de Polignac number, because 72191101 - 2⁷ = 72190973 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72891101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36095550 + 36095551.

It is an arithmetic number, because the mean of its divisors is an integer number (36095551).

Almost surely, 2^72191101 is an apocalyptic number.

It is an amenable number.

72191101 is a deficient number, since it is larger than the sum of its proper divisors (1).

72191101 is an equidigital number, since it uses as much as digits as its factorization.

72191101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 126, while the sum is 22.

The square root of 72191101 is about 8496.5346465486. The cubic root of 72191101 is about 416.3845006585.

The spelling of 72191101 in words is "seventy-two million, one hundred ninety-one thousand, one hundred one".