126921601 has 4 divisors (see below), whose sum is σ = 127586304. Its totient is φ = 126256900.

The previous prime is 126921593. The next prime is 126921607. The reversal of 126921601 is 106129621.

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: 106129621 = 13 ⋅8163817.

It is a cyclic number.

It is not a de Polignac number, because 126921601 - 2³ = 126921593 is a prime.

It is a super-2 number, since 2×126921601² = 32218185600806402, 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 126921601.

It is not an unprimeable number, because it can be changed into a prime (126921607) 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, 332065 + ... + 332446.

It is an arithmetic number, because the mean of its divisors is an integer number (31896576).

Almost surely, 2^126921601 is an apocalyptic number.

It is an amenable number.

126921601 is a deficient number, since it is larger than the sum of its proper divisors (664703).

126921601 is an equidigital number, since it uses as much as digits as its factorization.

126921601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 664702.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 126921601 is about 11265.9487394538. The cubic root of 126921601 is about 502.5491165904.

The spelling of 126921601 in words is "one hundred twenty-six million, nine hundred twenty-one thousand, six hundred one".