87645921573 has 24 divisors (see below), whose sum is σ = 135969009312. Its totient is φ = 50072922144.

The previous prime is 87645921533. The next prime is 87645921613. The reversal of 87645921573 is 37512954678.

It is an interprime number because it is at equal distance from previous prime (87645921533) and next prime (87645921613).

It is not a de Polignac number, because 87645921573 - 2⁶ = 87645921509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87645921533) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 673311 + ... + 792867.

It is an arithmetic number, because the mean of its divisors is an integer number (5665375388).

Almost surely, 2^87645921573 is an apocalyptic number.

It is an amenable number.

87645921573 is a deficient number, since it is larger than the sum of its proper divisors (48323087739).

87645921573 is a wasteful number, since it uses less digits than its factorization.

87645921573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124561 (or 124554 counting only the distinct ones).

The product of its digits is 12700800, while the sum is 57.

The spelling of 87645921573 in words is "eighty-seven billion, six hundred forty-five million, nine hundred twenty-one thousand, five hundred seventy-three".