1040402021 has 4 divisors (see below), whose sum is σ = 1045849344. Its totient is φ = 1034954700.

The previous prime is 1040402017. The next prime is 1040402029. The reversal of 1040402021 is 1202040401.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1202040401 = 29 ⋅41449669.

It is a cyclic number.

It is not a de Polignac number, because 1040402021 - 2² = 1040402017 is a prime.

It is a super-3 number, since 3×1040402021³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1040401987 and 1040402005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1040402029) 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, 2723375 + ... + 2723756.

It is an arithmetic number, because the mean of its divisors is an integer number (261462336).

Almost surely, 2^1040402021 is an apocalyptic number.

It is an amenable number.

1040402021 is a deficient number, since it is larger than the sum of its proper divisors (5447323).

1040402021 is an equidigital number, since it uses as much as digits as its factorization.

1040402021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5447322.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 1040402021 is about 32255.2634619530. The cubic root of 1040402021 is about 1013.2899355140.

Adding to 1040402021 its reverse (1202040401), we get a palindrome (2242442422).

The spelling of 1040402021 in words is "one billion, forty million, four hundred two thousand, twenty-one".