20857380 has 48 divisors (see below), whose sum is σ = 60419520. Its totient is φ = 5369728.

The previous prime is 20857373. The next prime is 20857387. The reversal of 20857380 is 8375802.

It is an interprime number because it is at equal distance from previous prime (20857373) and next prime (20857387).

It is not an unprimeable number, because it can be changed into a prime (20857387) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4254 + ... + 7733.

It is an arithmetic number, because the mean of its divisors is an integer number (1258740).

Almost surely, 2^20857380 is an apocalyptic number.

20857380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20857380 is an abundant number, since it is smaller than the sum of its proper divisors (39562140).

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

20857380 is a wasteful number, since it uses less digits than its factorization.

20857380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12028 (or 12026 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 20857380 is about 4566.9880665489. The cubic root of 20857380 is about 275.2664304938.

The spelling of 20857380 in words is "twenty million, eight hundred fifty-seven thousand, three hundred eighty".