20278379 has 4 divisors (see below), whose sum is σ = 22121880. Its totient is φ = 18434880.

The previous prime is 20278361. The next prime is 20278393. The reversal of 20278379 is 97387202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20278379 - 2¹² = 20274283 is a prime.

It is a super-2 number, since 2×20278379² = 822425309735282, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20278079) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 921734 + ... + 921755.

It is an arithmetic number, because the mean of its divisors is an integer number (5530470).

Almost surely, 2^20278379 is an apocalyptic number.

20278379 is a deficient number, since it is larger than the sum of its proper divisors (1843501).

20278379 is a wasteful number, since it uses less digits than its factorization.

20278379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1843500.

The product of its (nonzero) digits is 42336, while the sum is 38.

The square root of 20278379 is about 4503.1521182390. The cubic root of 20278379 is about 272.6953580466.

The spelling of 20278379 in words is "twenty million, two hundred seventy-eight thousand, three hundred seventy-nine".