1254405661 has 4 divisors (see below), whose sum is σ = 1256920000. Its totient is φ = 1251891324.

The previous prime is 1254405641. The next prime is 1254405689. The reversal of 1254405661 is 1665044521.

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.

It is a cyclic number.

It is not a de Polignac number, because 1254405661 - 2⁵ = 1254405629 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 (1254405641) 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, 1256421 + ... + 1257418.

It is an arithmetic number, because the mean of its divisors is an integer number (314230000).

Almost surely, 2^1254405661 is an apocalyptic number.

It is an amenable number.

1254405661 is a deficient number, since it is larger than the sum of its proper divisors (2514339).

1254405661 is an equidigital number, since it uses as much as digits as its factorization.

1254405661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2514338.

The product of its (nonzero) digits is 28800, while the sum is 34.

The square root of 1254405661 is about 35417.5897118932. The cubic root of 1254405661 is about 1078.4814222703.

The spelling of 1254405661 in words is "one billion, two hundred fifty-four million, four hundred five thousand, six hundred sixty-one".