1656236401 has 4 divisors (see below), whose sum is σ = 1658992804. Its totient is φ = 1653480000.

The previous prime is 1656236347. The next prime is 1656236419. The reversal of 1656236401 is 1046326561.

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 1324960000 + 331276401 = 36400^2 + 18201^2 .

It is a cyclic number.

It is not a de Polignac number, because 1656236401 - 2¹¹ = 1656234353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1656236801) 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, 1377300 + ... + 1378501.

It is an arithmetic number, because the mean of its divisors is an integer number (414748201).

Almost surely, 2^1656236401 is an apocalyptic number.

It is an amenable number.

1656236401 is a deficient number, since it is larger than the sum of its proper divisors (2756403).

1656236401 is an equidigital number, since it uses as much as digits as its factorization.

1656236401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2756402.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 1656236401 is about 40696.8844139204. The cubic root of 1656236401 is about 1183.1526345960.

The spelling of 1656236401 in words is "one billion, six hundred fifty-six million, two hundred thirty-six thousand, four hundred one".