126640531 has 8 divisors (see below), whose sum is σ = 134842320. Its totient is φ = 118522368.

The previous prime is 126640523. The next prime is 126640541. The reversal of 126640531 is 135046621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 126640531 - 2³ = 126640523 is a prime.

It is a super-2 number, since 2×126640531² = 32075648183923922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 126640531.

It is not an unprimeable number, because it can be changed into a prime (126640511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17766 + ... + 23851.

It is an arithmetic number, because the mean of its divisors is an integer number (16855290).

Almost surely, 2^126640531 is an apocalyptic number.

126640531 is a deficient number, since it is larger than the sum of its proper divisors (8201789).

126640531 is a wasteful number, since it uses less digits than its factorization.

126640531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41813.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 126640531 is about 11253.4675100611. The cubic root of 126640531 is about 502.1778746177.

It can be divided in two parts, 1266405 and 31, that added together give a triangular number (1266436 = T₁₅₉₁).

The spelling of 126640531 in words is "one hundred twenty-six million, six hundred forty thousand, five hundred thirty-one".