21381263400 has 96 divisors (see below), whose sum is σ = 75750776640. Its totient is φ = 4887144960.

The previous prime is 21381263329. The next prime is 21381263413. The reversal of 21381263400 is 436218312.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 2541189 + ... + 2549588.

It is an arithmetic number, because the mean of its divisors is an integer number (789070590).

Almost surely, 2^21381263400 is an apocalyptic number.

21381263400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21381263400 is an abundant number, since it is smaller than the sum of its proper divisors (54369513240).

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

21381263400 is a wasteful number, since it uses less digits than its factorization.

21381263400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5090803 (or 5090794 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The spelling of 21381263400 in words is "twenty-one billion, three hundred eighty-one million, two hundred sixty-three thousand, four hundred".