1821742425 has 18 divisors (see below), whose sum is σ = 3262943502. Its totient is φ = 971595840.

The previous prime is 1821742409. The next prime is 1821742441. The reversal of 1821742425 is 5242471281.

1821742425 is a `hidden beast` number, since 18 + 217 + 4 + 2 + 425 = 666.

It is an interprime number because it is at equal distance from previous prime (1821742409) and next prime (1821742441).

It can be written as a sum of positive squares in 3 ways, for example, as 13111641 + 1808630784 = 3621^2 + 42528^2 .

It is not a de Polignac number, because 1821742425 - 2⁴ = 1821742409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1821742425.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4048092 + ... + 4048541.

It is an arithmetic number, because the mean of its divisors is an integer number (181274639).

Almost surely, 2^1821742425 is an apocalyptic number.

1821742425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1821742425 is a deficient number, since it is larger than the sum of its proper divisors (1441201077).

1821742425 is a wasteful number, since it uses less digits than its factorization.

1821742425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8096649 (or 8096641 counting only the distinct ones).

The product of its digits is 35840, while the sum is 36.

The square root of 1821742425 is about 42681.8746659516. The cubic root of 1821742425 is about 1221.3186550461.

The spelling of 1821742425 in words is "one billion, eight hundred twenty-one million, seven hundred forty-two thousand, four hundred twenty-five".