1011005551 has 8 divisors (see below), whose sum is σ = 1041375104. Its totient is φ = 980947800.

The previous prime is 1011005539. The next prime is 1011005587. The reversal of 1011005551 is 1555001101.

It is a happy number.

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 1011005551 - 2¹³ = 1010997359 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 (1011005531) 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, 71361 + ... + 84346.

It is an arithmetic number, because the mean of its divisors is an integer number (130171888).

Almost surely, 2^1011005551 is an apocalyptic number.

1011005551 is a deficient number, since it is larger than the sum of its proper divisors (30369553).

1011005551 is a wasteful number, since it uses less digits than its factorization.

1011005551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155901.

The product of its (nonzero) digits is 125, while the sum is 19.

The square root of 1011005551 is about 31796.3134812827. The cubic root of 1011005551 is about 1003.6551406691.

Adding to 1011005551 its reverse (1555001101), we get a palindrome (2566006652).

The spelling of 1011005551 in words is "one billion, eleven million, five thousand, five hundred fifty-one".