8421725 has 12 divisors (see below), whose sum is σ = 11246676. Its totient is φ = 6218880.

The previous prime is 8421713. The next prime is 8421727. The reversal of 8421725 is 5271248.

It can be written as a sum of positive squares in 6 ways, for example, as 643204 + 7778521 = 802^2 + 2789^2 .

It is not a de Polignac number, because 8421725 - 2⁴ = 8421709 is a prime.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a d-powerful number, because it can be written as 8⁵ + 4¹¹ + 2²¹ + 1 + 7³ + 2²¹ + 5 .

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8421727) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12632 + ... + 13281.

It is an arithmetic number, because the mean of its divisors is an integer number (937223).

Almost surely, 2^8421725 is an apocalyptic number.

It is an amenable number.

8421725 is a deficient number, since it is larger than the sum of its proper divisors (2824951).

8421725 is a wasteful number, since it uses less digits than its factorization.

8421725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25936 (or 25931 counting only the distinct ones).

The product of its digits is 4480, while the sum is 29.

The square root of 8421725 is about 2902.0208476164. The cubic root of 8421725 is about 203.4543682032.

The spelling of 8421725 in words is "eight million, four hundred twenty-one thousand, seven hundred twenty-five".