1425456661 has 4 divisors (see below), whose sum is σ = 1426268800. Its totient is φ = 1424644524.

The previous prime is 1425456653. The next prime is 1425456667. The reversal of 1425456661 is 1666545241.

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: 1666545241 = 17 ⋅98032073.

It is a cyclic number.

It is not a de Polignac number, because 1425456661 - 2³ = 1425456653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1425456667) 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, 403431 + ... + 406948.

It is an arithmetic number, because the mean of its divisors is an integer number (356567200).

Almost surely, 2^1425456661 is an apocalyptic number.

It is an amenable number.

1425456661 is a deficient number, since it is larger than the sum of its proper divisors (812139).

1425456661 is an equidigital number, since it uses as much as digits as its factorization.

1425456661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812138.

The product of its digits is 172800, while the sum is 40.

The square root of 1425456661 is about 37755.2203145472. The cubic root of 1425456661 is about 1125.4287514081.

The spelling of 1425456661 in words is "one billion, four hundred twenty-five million, four hundred fifty-six thousand, six hundred sixty-one".