42129457 has 2 divisors, whose sum is σ = 42129458. Its totient is φ = 42129456.

The previous prime is 42129433. The next prime is 42129463. The reversal of 42129457 is 75492124.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24117921 + 18011536 = 4911^2 + 4244^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42129457 is a prime.

It is a super-2 number, since 2×42129457² = 3549782294229698, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (42129497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21064728 + 21064729.

It is an arithmetic number, because the mean of its divisors is an integer number (21064729).

Almost surely, 2^42129457 is an apocalyptic number.

It is an amenable number.

42129457 is a deficient number, since it is larger than the sum of its proper divisors (1).

42129457 is an equidigital number, since it uses as much as digits as its factorization.

42129457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 34.

The square root of 42129457 is about 6490.7208382429. The cubic root of 42129457 is about 347.9594378451.

The spelling of 42129457 in words is "forty-two million, one hundred twenty-nine thousand, four hundred fifty-seven".