56487821 has 16 divisors (see below), whose sum is σ = 64746864. Its totient is φ = 48820224.

The previous prime is 56487811. The next prime is 56487841. The reversal of 56487821 is 12878465.

56487821 = 5314² + 5315².

It can be written as a sum of positive squares in 8 ways, for example, as 5522500 + 50965321 = 2350^2 + 7139^2 .

It is a cyclic number.

It is not a de Polignac number, because 56487821 - 2⁶ = 56487757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56487811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50945 + ... + 52041.

It is an arithmetic number, because the mean of its divisors is an integer number (4046679).

Almost surely, 2^56487821 is an apocalyptic number.

56487821 is the 5315-th centered square number.

It is an amenable number.

56487821 is a deficient number, since it is larger than the sum of its proper divisors (8259043).

56487821 is a wasteful number, since it uses less digits than its factorization.

56487821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360.

The product of its digits is 107520, while the sum is 41.

The square root of 56487821 is about 7515.8380104949. The cubic root of 56487821 is about 383.6939406063.

The spelling of 56487821 in words is "fifty-six million, four hundred eighty-seven thousand, eight hundred twenty-one".