20701157 has 4 divisors (see below), whose sum is σ = 21415020. Its totient is φ = 19987296.

The previous prime is 20701139. The next prime is 20701159. The reversal of 20701157 is 75110702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75110702 = 2 ⋅37555351.

It can be written as a sum of positive squares in 2 ways, for example, as 14945956 + 5755201 = 3866^2 + 2399^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20701157 is a prime.

It is a super-2 number, since 2×20701157² = 857075802277298, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20701159) 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, 356888 + ... + 356945.

It is an arithmetic number, because the mean of its divisors is an integer number (5353755).

Almost surely, 2^20701157 is an apocalyptic number.

It is an amenable number.

20701157 is a deficient number, since it is larger than the sum of its proper divisors (713863).

20701157 is an equidigital number, since it uses as much as digits as its factorization.

20701157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713862.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 20701157 is about 4549.8524151889. The cubic root of 20701157 is about 274.5774535555.

Adding to 20701157 its reverse (75110702), we get a palindrome (95811859).

The spelling of 20701157 in words is "twenty million, seven hundred one thousand, one hundred fifty-seven".