21474025 has 6 divisors (see below), whose sum is σ = 26627822. Its totient is φ = 17179200.

The previous prime is 21473987. The next prime is 21474031. The reversal of 21474025 is 52047412.

It can be written as a sum of positive squares in 3 ways, for example, as 5184729 + 16289296 = 2277^2 + 4036^2 .

It is not a de Polignac number, because 21474025 - 2¹⁷ = 21342953 is a prime.

It is a super-2 number, since 2×21474025² = 922267499401250, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 858961 = 21474025 / (2 + 1 + 4 + 7 + 4 + 0 + 2 + 5).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 429456 + ... + 429505.

Almost surely, 2^21474025 is an apocalyptic number.

21474025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21474025 is a deficient number, since it is larger than the sum of its proper divisors (5153797).

21474025 is an equidigital number, since it uses as much as digits as its factorization.

21474025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 858971 (or 858966 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 21474025 is about 4634.0074449660. The cubic root of 21474025 is about 277.9528628048.

The spelling of 21474025 in words is "twenty-one million, four hundred seventy-four thousand, twenty-five".