1656474451 has 4 divisors (see below), whose sum is σ = 1656801432. Its totient is φ = 1656147472.

The previous prime is 1656474427. The next prime is 1656474493. The reversal of 1656474451 is 1544746561.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1656474451 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1656474398 and 1656474407.

It is not an unprimeable number, because it can be changed into a prime (1656474401) 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, 155770 + ... + 166063.

It is an arithmetic number, because the mean of its divisors is an integer number (414200358).

Almost surely, 2^1656474451 is an apocalyptic number.

1656474451 is a deficient number, since it is larger than the sum of its proper divisors (326981).

1656474451 is an equidigital number, since it uses as much as digits as its factorization.

1656474451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326980.

The product of its digits is 403200, while the sum is 43.

The square root of 1656474451 is about 40699.8089798957. The cubic root of 1656474451 is about 1183.2093165189.

The spelling of 1656474451 in words is "one billion, six hundred fifty-six million, four hundred seventy-four thousand, four hundred fifty-one".