20521470 has 32 divisors (see below), whose sum is σ = 49576608. Its totient is φ = 5436288.

The previous prime is 20521453. The next prime is 20521489. The reversal of 20521470 is 7412502.

It is a super-2 number, since 2×20521470² = 842261461921800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2532 + ... + 6888.

It is an arithmetic number, because the mean of its divisors is an integer number (1549269).

Almost surely, 2^20521470 is an apocalyptic number.

20521470 is an abundant number, since it is smaller than the sum of its proper divisors (29055138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20521470 is a wasteful number, since it uses less digits than its factorization.

20521470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4524.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 20521470 is about 4530.0629134704. The cubic root of 20521470 is about 273.7806954592.

Adding to 20521470 its reverse (7412502), we get a palindrome (27933972).

The spelling of 20521470 in words is "twenty million, five hundred twenty-one thousand, four hundred seventy".