1534166821 has 4 divisors (see below), whose sum is σ = 1673636544. Its totient is φ = 1394697100.

The previous prime is 1534166813. The next prime is 1534166827. The reversal of 1534166821 is 1286614351.

It is a happy number.

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: 1286614351 = 11 ⋅116964941.

It is a cyclic number.

It is not a de Polignac number, because 1534166821 - 2³ = 1534166813 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 (1534166827) 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, 69734845 + ... + 69734866.

It is an arithmetic number, because the mean of its divisors is an integer number (418409136).

Almost surely, 2^1534166821 is an apocalyptic number.

1534166821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1534166821 is a deficient number, since it is larger than the sum of its proper divisors (139469723).

1534166821 is a wasteful number, since it uses less digits than its factorization.

1534166821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139469722.

The product of its digits is 34560, while the sum is 37.

The square root of 1534166821 is about 39168.4416463050. The cubic root of 1534166821 is about 1153.3404628199.

The spelling of 1534166821 in words is "one billion, five hundred thirty-four million, one hundred sixty-six thousand, eight hundred twenty-one".