21471597 has 12 divisors (see below), whose sum is σ = 35445280. Its totient is φ = 12269448.

The previous prime is 21471589. The next prime is 21471631. The reversal of 21471597 is 79517412.

It is a happy number.

21471597 is a `hidden beast` number, since 21 + 47 + 1 + 597 = 666.

It is not a de Polignac number, because 21471597 - 2³ = 21471589 is a prime.

It is a super-2 number, since 2×21471597² = 922058955460818, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21471097) 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 11 ways as a sum of consecutive naturals, for example, 170347 + ... + 170472.

Almost surely, 2^21471597 is an apocalyptic number.

It is an amenable number.

21471597 is a deficient number, since it is larger than the sum of its proper divisors (13973683).

21471597 is a wasteful number, since it uses less digits than its factorization.

21471597 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340832 (or 340829 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 21471597 is about 4633.7454612872. The cubic root of 21471597 is about 277.9423866600.

The spelling of 21471597 in words is "twenty-one million, four hundred seventy-one thousand, five hundred ninety-seven".