1156406421 has 4 divisors (see below), whose sum is σ = 1541875232. Its totient is φ = 770937612.

The previous prime is 1156406393. The next prime is 1156406483. The reversal of 1156406421 is 1246046511.

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: 1246046511 = 3 ⋅415348837.

It is not a de Polignac number, because 1156406421 - 2²⁷ = 1022188693 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 (1156406491) 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, 192734401 + ... + 192734406.

It is an arithmetic number, because the mean of its divisors is an integer number (385468808).

Almost surely, 2^1156406421 is an apocalyptic number.

It is an amenable number.

1156406421 is a deficient number, since it is larger than the sum of its proper divisors (385468811).

1156406421 is an equidigital number, since it uses as much as digits as its factorization.

1156406421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385468810.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 1156406421 is about 34005.9762541821. The cubic root of 1156406421 is about 1049.6314416233.

The spelling of 1156406421 in words is "one billion, one hundred fifty-six million, four hundred six thousand, four hundred twenty-one".