72240251 has 2 divisors, whose sum is σ = 72240252. Its totient is φ = 72240250.

The previous prime is 72240241. The next prime is 72240257. The reversal of 72240251 is 15204227.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (15204227) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72240251 - 2⁶ = 72240187 is a prime.

It is equal to p_4242074 and since 72240251 and 4242074 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72240257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36120125 + 36120126.

It is an arithmetic number, because the mean of its divisors is an integer number (36120126).

Almost surely, 2^72240251 is an apocalyptic number.

72240251 is a deficient number, since it is larger than the sum of its proper divisors (1).

72240251 is an equidigital number, since it uses as much as digits as its factorization.

72240251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 72240251 is about 8499.4265100653. The cubic root of 72240251 is about 416.4789751630.

Adding to 72240251 its reverse (15204227), we get a palindrome (87444478).

The spelling of 72240251 in words is "seventy-two million, two hundred forty thousand, two hundred fifty-one".