20951340 has 48 divisors (see below), whose sum is σ = 60691680. Its totient is φ = 5393920.

The previous prime is 20951323. The next prime is 20951347. The reversal of 20951340 is 4315902.

It is a self number, because there is not a number n which added to its sum of digits gives 20951340.

It is not an unprimeable number, because it can be changed into a prime (20951347) 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, 4281 + ... + 7760.

It is an arithmetic number, because the mean of its divisors is an integer number (1264410).

Almost surely, 2^20951340 is an apocalyptic number.

20951340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20951340 is an abundant number, since it is smaller than the sum of its proper divisors (39740340).

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

20951340 is a wasteful number, since it uses less digits than its factorization.

20951340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12082 (or 12080 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 20951340 is about 4577.2633745503. The cubic root of 20951340 is about 275.6791587878.

The spelling of 20951340 in words is "twenty million, nine hundred fifty-one thousand, three hundred forty".