1821897045 has 24 divisors (see below), whose sum is σ = 3295259136. Its totient is φ = 929431008.

The previous prime is 1821897043. The next prime is 1821897059. The reversal of 1821897045 is 5407981281.

It is not a de Polignac number, because 1821897045 - 2¹ = 1821897043 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821897043) 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, 879109 + ... + 881178.

It is an arithmetic number, because the mean of its divisors is an integer number (137302464).

Almost surely, 2^1821897045 is an apocalyptic number.

1821897045 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1821897045 is a deficient number, since it is larger than the sum of its proper divisors (1473362091).

1821897045 is a wasteful number, since it uses less digits than its factorization.

1821897045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1760321 (or 1760318 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The square root of 1821897045 is about 42683.6859350267. The cubic root of 1821897045 is about 1221.3532071221.

The spelling of 1821897045 in words is "one billion, eight hundred twenty-one million, eight hundred ninety-seven thousand, forty-five".