20481639 has 8 divisors (see below), whose sum is σ = 28746240. Its totient is φ = 12935736.

The previous prime is 20481623. The next prime is 20481641. The reversal of 20481639 is 93618402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20481639 - 2⁴ = 20481623 is a prime.

It is a super-2 number, since 2×20481639² = 838995072252642, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20481649) 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, 179607 + ... + 179720.

It is an arithmetic number, because the mean of its divisors is an integer number (3593280).

Almost surely, 2^20481639 is an apocalyptic number.

20481639 is a deficient number, since it is larger than the sum of its proper divisors (8264601).

20481639 is a wasteful number, since it uses less digits than its factorization.

20481639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359349.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 20481639 is about 4525.6644815983. The cubic root of 20481639 is about 273.6034498428.

The spelling of 20481639 in words is "twenty million, four hundred eighty-one thousand, six hundred thirty-nine".