20521516 has 24 divisors (see below), whose sum is σ = 38840256. Its totient is φ = 9450240.

The previous prime is 20521507. The next prime is 20521519. The reversal of 20521516 is 61512502.

It is a super-2 number, since 2×20521516² = 842265237876512, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20521519) 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, 15 + ... + 6406.

It is an arithmetic number, because the mean of its divisors is an integer number (1618344).

Almost surely, 2^20521516 is an apocalyptic number.

It is an amenable number.

20521516 is a deficient number, since it is larger than the sum of its proper divisors (18318740).

20521516 is a wasteful number, since it uses less digits than its factorization.

20521516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6489 (or 6487 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 20521516 is about 4530.0679906597. The cubic root of 20521516 is about 273.7809000239.

The spelling of 20521516 in words is "twenty million, five hundred twenty-one thousand, five hundred sixteen".