213840157 has 4 divisors (see below), whose sum is σ = 214601436. Its totient is φ = 213078880.

The previous prime is 213840103. The next prime is 213840163. The reversal of 213840157 is 751048312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81613156 + 132227001 = 9034^2 + 11499^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213840157 is a prime.

It is a super-2 number, since 2×213840157² = 91455225491569298, 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 (213840167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 380218 + ... + 380779.

It is an arithmetic number, because the mean of its divisors is an integer number (53650359).

Almost surely, 2^213840157 is an apocalyptic number.

It is an amenable number.

213840157 is a deficient number, since it is larger than the sum of its proper divisors (761279).

213840157 is an equidigital number, since it uses as much as digits as its factorization.

213840157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 761278.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 213840157 is about 14623.2744965004. The cubic root of 213840157 is about 597.9934423952.

Adding to 213840157 its reverse (751048312), we get a palindrome (964888469).

The spelling of 213840157 in words is "two hundred thirteen million, eight hundred forty thousand, one hundred fifty-seven".