1551042421 has 8 divisors (see below), whose sum is σ = 1619003520. Its totient is φ = 1483125072.

The previous prime is 1551042401. The next prime is 1551042439. The reversal of 1551042421 is 1242401551.

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 1551042421 - 2²³ = 1542653813 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 (1551042401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76471 + ... + 94603.

It is an arithmetic number, because the mean of its divisors is an integer number (202375440).

Almost surely, 2^1551042421 is an apocalyptic number.

It is an amenable number.

1551042421 is a deficient number, since it is larger than the sum of its proper divisors (67961099).

1551042421 is a wasteful number, since it uses less digits than its factorization.

1551042421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21875.

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 1551042421 is about 39383.2759048812. The cubic root of 1551042421 is about 1157.5539074297.

Adding to 1551042421 its reverse (1242401551), we get a palindrome (2793443972).

The spelling of 1551042421 in words is "one billion, five hundred fifty-one million, forty-two thousand, four hundred twenty-one".