20157740 has 12 divisors (see below), whose sum is σ = 42331296. Its totient is φ = 8063088.

The previous prime is 20157737. The next prime is 20157743. The reversal of 20157740 is 4775102.

It is an interprime number because it is at equal distance from previous prime (20157737) and next prime (20157743).

It is not an unprimeable number, because it can be changed into a prime (20157743) 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, 503924 + ... + 503963.

It is an arithmetic number, because the mean of its divisors is an integer number (3527608).

Almost surely, 2^20157740 is an apocalyptic number.

20157740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20157740 is an abundant number, since it is smaller than the sum of its proper divisors (22173556).

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

20157740 is a wasteful number, since it uses less digits than its factorization.

20157740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1007896 (or 1007894 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 20157740 is about 4489.7371860723. The cubic root of 20157740 is about 272.1535141204.

The spelling of 20157740 in words is "twenty million, one hundred fifty-seven thousand, seven hundred forty".