1031521421 has 8 divisors (see below), whose sum is σ = 1182224064. Its totient is φ = 881654400.

The previous prime is 1031521349. The next prime is 1031521433. The reversal of 1031521421 is 1241251301.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1031521421 - 2¹⁸ = 1031259277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1031521393 and 1031521402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1031521471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 206255 + ... + 211196.

It is an arithmetic number, because the mean of its divisors is an integer number (147778008).

Almost surely, 2^1031521421 is an apocalyptic number.

It is an amenable number.

1031521421 is a deficient number, since it is larger than the sum of its proper divisors (150702643).

1031521421 is an equidigital number, since it uses as much as digits as its factorization.

1031521421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417811.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 1031521421 is about 32117.3071878699. The cubic root of 1031521421 is about 1010.3986339386.

Adding to 1031521421 its reverse (1241251301), we get a palindrome (2272772722).

The spelling of 1031521421 in words is "one billion, thirty-one million, five hundred twenty-one thousand, four hundred twenty-one".