1405040621 has 6 divisors (see below), whose sum is σ = 1451827566. Its totient is φ = 1359715800.

The previous prime is 1405040617. The next prime is 1405040657. The reversal of 1405040621 is 1260405041.

It can be written as a sum of positive squares in only one way, i.e., 1150159396 + 254881225 = 33914^2 + 15965^2 .

It is not a de Polignac number, because 1405040621 - 2² = 1405040617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1405040821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 730070 + ... + 731991.

It is an arithmetic number, because the mean of its divisors is an integer number (241971261).

Almost surely, 2^1405040621 is an apocalyptic number.

It is an amenable number.

1405040621 is a deficient number, since it is larger than the sum of its proper divisors (46786945).

1405040621 is an equidigital number, since it uses as much as digits as its factorization.

1405040621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1462123 (or 1462092 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 1405040621 is about 37483.8714782772. The cubic root of 1405040621 is about 1120.0299261243.

Adding to 1405040621 its reverse (1260405041), we get a palindrome (2665445662).

The spelling of 1405040621 in words is "one billion, four hundred five million, forty thousand, six hundred twenty-one".