81007153 has 4 divisors (see below), whose sum is σ = 82032640. Its totient is φ = 79981668.

The previous prime is 81007139. The next prime is 81007183. The reversal of 81007153 is 35170018.

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.

It is a cyclic number.

It is not a de Polignac number, because 81007153 - 2²¹ = 78910001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81007183) 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, 512625 + ... + 512782.

It is an arithmetic number, because the mean of its divisors is an integer number (20508160).

Almost surely, 2^81007153 is an apocalyptic number.

It is an amenable number.

81007153 is a deficient number, since it is larger than the sum of its proper divisors (1025487).

81007153 is a wasteful number, since it uses less digits than its factorization.

81007153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1025486.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 81007153 is about 9000.3973801161. The cubic root of 81007153 is about 432.6876070274.

The spelling of 81007153 in words is "eighty-one million, seven thousand, one hundred fifty-three".