21471075 has 60 divisors (see below), whose sum is σ = 41591088. Its totient is φ = 10929600.

The previous prime is 21471067. The next prime is 21471077. The reversal of 21471075 is 57017412.

It is not a de Polignac number, because 21471075 - 2³ = 21471067 is a prime.

It is a super-2 number, since 2×21471075² = 922014123311250, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (21471077) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 46345 + ... + 46805.

Almost surely, 2^21471075 is an apocalyptic number.

21471075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21471075 is a deficient number, since it is larger than the sum of its proper divisors (20120013).

21471075 is a wasteful number, since it uses less digits than its factorization.

21471075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506 (or 492 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 21471075 is about 4633.6891350197. The cubic root of 21471075 is about 277.9401342720.

Adding to 21471075 its reverse (57017412), we get a palindrome (78488487).

It can be divided in two parts, 214 and 71075, that added together give a square (71289 = 267²).

The spelling of 21471075 in words is "twenty-one million, four hundred seventy-one thousand, seventy-five".