1921775625 has 400 divisors, whose sum is σ = 4898931840. Its totient is φ = 725760000.

The previous prime is 1921775623. The next prime is 1921775629. The reversal of 1921775625 is 5265771291.

1921775625 is a `hidden beast` number, since 1 + 9 + 2 + 17 + 7 + 5 + 625 = 666.

It is not a de Polignac number, because 1921775625 - 2¹ = 1921775623 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

Its product of digits (264600) is a multiple of the sum of its prime divisors (72).

It is not an unprimeable number, because it can be changed into a prime (1921775623) by changing a digit.

It is a polite number, since it can be written in 399 ways as a sum of consecutive naturals, for example, 66268111 + ... + 66268139.

Almost surely, 2^1921775625 is an apocalyptic number.

1921775625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1921775625 is an abundant number, since it is smaller than the sum of its proper divisors (2977156215).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1921775625 is a wasteful number, since it uses less digits than its factorization.

1921775625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 72 counting only the distinct ones).

The product of its digits is 264600, while the sum is 45.

The square root of 1921775625 is about 43838.0613736511. The cubic root of 1921775625 is about 1243.2760287558.

The spelling of 1921775625 in words is "one billion, nine hundred twenty-one million, seven hundred seventy-five thousand, six hundred twenty-five".