53821639 has 4 divisors (see below), whose sum is σ = 53971920. Its totient is φ = 53671360.

The previous prime is 53821613. The next prime is 53821657. The reversal of 53821639 is 93612835.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 53821639 - 2¹⁵ = 53788871 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 53821598 and 53821607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53821139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74602 + ... + 75319.

It is an arithmetic number, because the mean of its divisors is an integer number (13492980).

Almost surely, 2^53821639 is an apocalyptic number.

53821639 is a deficient number, since it is larger than the sum of its proper divisors (150281).

53821639 is a wasteful number, since it uses less digits than its factorization.

53821639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150280.

The product of its digits is 38880, while the sum is 37.

The square root of 53821639 is about 7336.3232616891. The cubic root of 53821639 is about 377.5597063581.

It can be divided in two parts, 5382 and 1639, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 53821639 in words is "fifty-three million, eight hundred twenty-one thousand, six hundred thirty-nine".