72618261 has 4 divisors (see below), whose sum is σ = 96824352. Its totient is φ = 48412172.

The previous prime is 72618241. The next prime is 72618263. The reversal of 72618261 is 16281627.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16281627 = 3 ⋅5427209.

It is a cyclic number.

It is not a de Polignac number, because 72618261 - 2¹¹ = 72616213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72618263) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12103041 + ... + 12103046.

It is an arithmetic number, because the mean of its divisors is an integer number (24206088).

Almost surely, 2^72618261 is an apocalyptic number.

It is an amenable number.

72618261 is a deficient number, since it is larger than the sum of its proper divisors (24206091).

72618261 is a wasteful number, since it uses less digits than its factorization.

72618261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24206090.

The product of its digits is 8064, while the sum is 33.

The square root of 72618261 is about 8521.6348783552. The cubic root of 72618261 is about 417.2041452798.

Adding to 72618261 its reverse (16281627), we get a palindrome (88899888).

The spelling of 72618261 in words is "seventy-two million, six hundred eighteen thousand, two hundred sixty-one".