72007561 has 8 divisors (see below), whose sum is σ = 73471104. Its totient is φ = 70556640.

The previous prime is 72007541. The next prime is 72007567. The reversal of 72007561 is 16570027.

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 72007561 - 2⁷ = 72007433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72007567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8821 + ... + 14893.

It is an arithmetic number, because the mean of its divisors is an integer number (9183888).

Almost surely, 2^72007561 is an apocalyptic number.

72007561 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

72007561 is a deficient number, since it is larger than the sum of its proper divisors (1463543).

72007561 is a wasteful number, since it uses less digits than its factorization.

72007561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6311.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 72007561 is about 8485.7268987400. The cubic root of 72007561 is about 416.0313266134.

Adding to 72007561 its reverse (16570027), we get a palindrome (88577588).

The spelling of 72007561 in words is "seventy-two million, seven thousand, five hundred sixty-one".