21378951675 has 36 divisors (see below), whose sum is σ = 39710314280. Its totient is φ = 11402104320.

The previous prime is 21378951619. The next prime is 21378951703. The reversal of 21378951675 is 57615987312.

21378951675 is a `hidden beast` number, since 21 + 37 + 8 + 9 + 516 + 75 = 666.

It is not a de Polignac number, because 21378951675 - 2¹⁸ = 21378689531 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1753510 + ... + 1765659.

Almost surely, 2^21378951675 is an apocalyptic number.

21378951675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21378951675 is a deficient number, since it is larger than the sum of its proper divisors (18331362605).

21378951675 is an equidigital number, since it uses as much as digits as its factorization.

21378951675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3519194 (or 3519177 counting only the distinct ones).

The product of its digits is 3175200, while the sum is 54.

The spelling of 21378951675 in words is "twenty-one billion, three hundred seventy-eight million, nine hundred fifty-one thousand, six hundred seventy-five".