1253645973 has 24 divisors (see below), whose sum is σ = 1907590880. Its totient is φ = 791169120.

The previous prime is 1253645933. The next prime is 1253645999. The reversal of 1253645973 is 3795463521.

1253645973 is a `hidden beast` number, since 1 + 2 + 53 + 6 + 4 + 597 + 3 = 666.

It is not a de Polignac number, because 1253645973 - 2⁹ = 1253645461 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1253645933) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 349278 + ... + 352848.

Almost surely, 2^1253645973 is an apocalyptic number.

It is an amenable number.

1253645973 is a deficient number, since it is larger than the sum of its proper divisors (653944907).

1253645973 is a wasteful number, since it uses less digits than its factorization.

1253645973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5649 (or 5646 counting only the distinct ones).

The product of its digits is 680400, while the sum is 45.

The square root of 1253645973 is about 35406.8633600888. The cubic root of 1253645973 is about 1078.2636631430.

The spelling of 1253645973 in words is "one billion, two hundred fifty-three million, six hundred forty-five thousand, nine hundred seventy-three".