21067727400 has 120 divisors (see below), whose sum is σ = 73171394670. Its totient is φ = 5618056320.

The previous prime is 21067727399. The next prime is 21067727437. The reversal of 21067727400 is 472776012.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 19565854884 + 1501872516 = 139878^2 + 38754^2 .

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 (36).

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 634039 + ... + 666438.

Almost surely, 2^21067727400 is an apocalyptic number.

21067727400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21067727400 is an abundant number, since it is smaller than the sum of its proper divisors (52103667270).

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

21067727400 is a wasteful number, since it uses less digits than its factorization.

21067727400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1300505 (or 1300487 counting only the distinct ones).

The product of its (nonzero) digits is 32928, while the sum is 36.

The spelling of 21067727400 in words is "twenty-one billion, sixty-seven million, seven hundred twenty-seven thousand, four hundred".