20851377 has 8 divisors (see below), whose sum is σ = 28760640. Its totient is φ = 13421520.

The previous prime is 20851361. The next prime is 20851399. The reversal of 20851377 is 77315802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20851377 - 2⁴ = 20851361 is a prime.

It is a super-2 number, since 2×20851377² = 869559845592258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20851277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 119749 + ... + 119922.

It is an arithmetic number, because the mean of its divisors is an integer number (3595080).

Almost surely, 2^20851377 is an apocalyptic number.

It is an amenable number.

20851377 is a deficient number, since it is larger than the sum of its proper divisors (7909263).

20851377 is a wasteful number, since it uses less digits than its factorization.

20851377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239703.

The product of its (nonzero) digits is 11760, while the sum is 33.

The square root of 20851377 is about 4566.3308027343. The cubic root of 20851377 is about 275.2400196513.

The spelling of 20851377 in words is "twenty million, eight hundred fifty-one thousand, three hundred seventy-seven".