21072485 has 16 divisors (see below), whose sum is σ = 30157056. Its totient is φ = 13820928.

The previous prime is 21072481. The next prime is 21072487. The reversal of 21072485 is 58427012.

It is a cyclic number.

It is not a de Polignac number, because 21072485 - 2² = 21072481 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21072481) 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, 12284 + ... + 13893.

It is an arithmetic number, because the mean of its divisors is an integer number (1884816).

Almost surely, 2^21072485 is an apocalyptic number.

It is an amenable number.

21072485 is a deficient number, since it is larger than the sum of its proper divisors (9084571).

21072485 is a wasteful number, since it uses less digits than its factorization.

21072485 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26212.

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

The square root of 21072485 is about 4590.4776439931. The cubic root of 21072485 is about 276.2094826704.

Adding to 21072485 its reverse (58427012), we get a palindrome (79499497).

The spelling of 21072485 in words is "twenty-one million, seventy-two thousand, four hundred eighty-five".