157021 has 4 divisors (see below), whose sum is σ = 163872. Its totient is φ = 150172.

The previous prime is 157019. The next prime is 157037. The reversal of 157021 is 120751.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120751 = 17 ⋅7103.

It is a cyclic number.

It is not a de Polignac number, because 157021 - 2¹ = 157019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 156986 and 157004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157051) 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, 3391 + ... + 3436.

It is an arithmetic number, because the mean of its divisors is an integer number (40968).

2¹⁵⁷⁰²¹ is an apocalyptic number.

It is an amenable number.

157021 is a deficient number, since it is larger than the sum of its proper divisors (6851).

157021 is an equidigital number, since it uses as much as digits as its factorization.

157021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6850.

The product of its (nonzero) digits is 70, while the sum is 16.

The square root of 157021 is about 396.2587538465. The cubic root of 157021 is about 53.9493122900.

Adding to 157021 its reverse (120751), we get a palindrome (277772).

The spelling of 157021 in words is "one hundred fifty-seven thousand, twenty-one".