21527470 has 16 divisors (see below), whose sum is σ = 38877408. Its totient is φ = 8582560.

The previous prime is 21527459. The next prime is 21527479. The reversal of 21527470 is 7472512.

21527470 = 86² + 87² + ... + 402².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21527479) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 226 + ... + 6565.

It is an arithmetic number, because the mean of its divisors is an integer number (2429838).

Almost surely, 2^21527470 is an apocalyptic number.

21527470 is a deficient number, since it is larger than the sum of its proper divisors (17349938).

21527470 is a wasteful number, since it uses less digits than its factorization.

21527470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7115.

The product of its (nonzero) digits is 3920, while the sum is 28.

The square root of 21527470 is about 4639.7704684607. The cubic root of 21527470 is about 278.1832633903.

Adding to 21527470 its reverse (7472512), we get a palindrome (28999982).

The spelling of 21527470 in words is "twenty-one million, five hundred twenty-seven thousand, four hundred seventy".