20461520 has 40 divisors (see below), whose sum is σ = 47809440. Its totient is φ = 8144000.

The previous prime is 20461517. The next prime is 20461541. The reversal of 20461520 is 2516402.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 20461492 and 20461501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19571 + ... + 20589.

It is an arithmetic number, because the mean of its divisors is an integer number (1195236).

Almost surely, 2^20461520 is an apocalyptic number.

20461520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20461520 is an abundant number, since it is smaller than the sum of its proper divisors (27347920).

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

20461520 is a wasteful number, since it uses less digits than its factorization.

20461520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1283 (or 1277 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20461520 is about 4523.4411679605. The cubic root of 20461520 is about 273.5138341114.

Adding to 20461520 its reverse (2516402), we get a palindrome (22977922).

The spelling of 20461520 in words is "twenty million, four hundred sixty-one thousand, five hundred twenty".