72401551 has 8 divisors (see below), whose sum is σ = 75485520. Its totient is φ = 69381312.

The previous prime is 72401509. The next prime is 72401561. The reversal of 72401551 is 15510427.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72401551 - 2¹³ = 72393359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72401501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13606 + ... + 18163.

It is an arithmetic number, because the mean of its divisors is an integer number (9435690).

Almost surely, 2^72401551 is an apocalyptic number.

72401551 is a deficient number, since it is larger than the sum of its proper divisors (3083969).

72401551 is a wasteful number, since it uses less digits than its factorization.

72401551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31865.

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 72401551 is about 8508.9100947184. The cubic root of 72401551 is about 416.7887199415.

Adding to 72401551 its reverse (15510427), we get a palindrome (87911978).

The spelling of 72401551 in words is "seventy-two million, four hundred one thousand, five hundred fifty-one".