21010124400 has 120 divisors (see below), whose sum is σ = 69121562544. Its totient is φ = 5451264000.

The previous prime is 21010124389. The next prime is 21010124411. The reversal of 21010124400 is 442101012.

It is an interprime number because it is at equal distance from previous prime (21010124389) and next prime (21010124411).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21010124400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 192201 + ... + 281000.

Almost surely, 2^21010124400 is an apocalyptic number.

21010124400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010124400 is an abundant number, since it is smaller than the sum of its proper divisors (48111438144).

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

21010124400 is a wasteful number, since it uses less digits than its factorization.

21010124400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473259 (or 473248 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21010124400 its reverse (442101012), we get a palindrome (21452225412).

The spelling of 21010124400 in words is "twenty-one billion, ten million, one hundred twenty-four thousand, four hundred".