21838953240 has 128 divisors (see below), whose sum is σ = 78396292800. Its totient is φ = 5375738880.

The previous prime is 21838953217. The next prime is 21838953251. The reversal of 21838953240 is 4235983812.

21838953240 is a `hidden beast` number, since 21 + 8 + 389 + 5 + 3 + 240 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 763701 + ... + 791780.

Almost surely, 2^21838953240 is an apocalyptic number.

21838953240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21838953240 is an abundant number, since it is smaller than the sum of its proper divisors (56557339560).

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

21838953240 is a wasteful number, since it uses less digits than its factorization.

21838953240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1555514 (or 1555504 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 21838953240 in words is "twenty-one billion, eight hundred thirty-eight million, nine hundred fifty-three thousand, two hundred forty".