8157640 has 32 divisors (see below), whose sum is σ = 19154880. Its totient is φ = 3120832.

The previous prime is 8157629. The next prime is 8157641. The reversal of 8157640 is 467518.

8157640 = T₂₀₁ + T₂₀₂ + ... + T₃₈₄.

It is not an unprimeable number, because it can be changed into a prime (8157641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3514 + ... + 5353.

It is an arithmetic number, because the mean of its divisors is an integer number (598590).

Almost surely, 2^8157640 is an apocalyptic number.

It is an amenable number.

8157640 is an abundant number, since it is smaller than the sum of its proper divisors (10997240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8157640 is a wasteful number, since it uses less digits than its factorization.

8157640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8901 (or 8897 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 8157640 is about 2856.1582589205. The cubic root of 8157640 is about 201.3051313021.

The spelling of 8157640 in words is "eight million, one hundred fifty-seven thousand, six hundred forty".