42721525 has 24 divisors (see below), whose sum is σ = 66049344. Its totient is φ = 26630400.

The previous prime is 42721517. The next prime is 42721529. The reversal of 42721525 is 52512724.

It is not a de Polignac number, because 42721525 - 2³ = 42721517 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42721493 and 42721502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42721529) 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, 9172 + ... + 13021.

It is an arithmetic number, because the mean of its divisors is an integer number (2752056).

Almost surely, 2^42721525 is an apocalyptic number.

It is an amenable number.

42721525 is a deficient number, since it is larger than the sum of its proper divisors (23327819).

42721525 is a wasteful number, since it uses less digits than its factorization.

42721525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22221 (or 22216 counting only the distinct ones).

The product of its digits is 5600, while the sum is 28.

The square root of 42721525 is about 6536.1705149116. The cubic root of 42721525 is about 349.5818816571.

It can be divided in two parts, 427 and 21525, that added together give a cube (21952 = 28³).

The spelling of 42721525 in words is "forty-two million, seven hundred twenty-one thousand, five hundred twenty-five".