4545400021 has 4 divisors (see below), whose sum is σ = 4564260844. Its totient is φ = 4526539200.

The previous prime is 4545400019. The next prime is 4545400063. The reversal of 4545400021 is 1200045454.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3463911025 + 1081488996 = 58855^2 + 32886^2 .

It is a cyclic number.

It is not a de Polignac number, because 4545400021 - 2¹ = 4545400019 is a prime.

It is a super-2 number, since 2×4545400021² = 41321322701813600882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4545400621) 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, 9430050 + ... + 9430531.

It is an arithmetic number, because the mean of its divisors is an integer number (1141065211).

Almost surely, 2^4545400021 is an apocalyptic number.

It is an amenable number.

4545400021 is a deficient number, since it is larger than the sum of its proper divisors (18860823).

4545400021 is a wasteful number, since it uses less digits than its factorization.

4545400021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18860822.

The product of its (nonzero) digits is 3200, while the sum is 25.

The square root of 4545400021 is about 67419.5818809343. The cubic root of 4545400021 is about 1656.4971888691.

Adding to 4545400021 its reverse (1200045454), we get a palindrome (5745445475).

The spelling of 4545400021 in words is "four billion, five hundred forty-five million, four hundred thousand, twenty-one".