8157720 has 64 divisors (see below), whose sum is σ = 24685920. Its totient is φ = 2156544.

The previous prime is 8157701. The next prime is 8157727. The reversal of 8157720 is 277518.

It is a happy number.

8157720 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8157727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18624 + ... + 19056.

Almost surely, 2^8157720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8157720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12342960).

8157720 is an abundant number, since it is smaller than the sum of its proper divisors (16528200).

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

8157720 is a wasteful number, since it uses less digits than its factorization.

8157720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 8157720 is about 2856.1722637124. The cubic root of 8157720 is about 201.3057893502.

The spelling of 8157720 in words is "eight million, one hundred fifty-seven thousand, seven hundred twenty".