21078941400 has 144 divisors (see below), whose sum is σ = 77225648760. Its totient is φ = 5110041600.

The previous prime is 21078941383. The next prime is 21078941407. The reversal of 21078941400 is 414987012.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21078941407) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 512497 + ... + 552096.

Almost surely, 2^21078941400 is an apocalyptic number.

21078941400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21078941400 is an abundant number, since it is smaller than the sum of its proper divisors (56146707360).

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

21078941400 is a wasteful number, since it uses less digits than its factorization.

21078941400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1064626 (or 1064614 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 21078941400 in words is "twenty-one billion, seventy-eight million, nine hundred forty-one thousand, four hundred".