51151890 has 48 divisors (see below), whose sum is σ = 125330688. Its totient is φ = 13361088.

The previous prime is 51151873. The next prime is 51151907. The reversal of 51151890 is 9815115.

It is an interprime number because it is at equal distance from previous prime (51151873) and next prime (51151907).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 83967 + ... + 84573.

It is an arithmetic number, because the mean of its divisors is an integer number (2611056).

Almost surely, 2^51151890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51151890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62665344).

51151890 is an abundant number, since it is smaller than the sum of its proper divisors (74178798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51151890 is a wasteful number, since it uses less digits than its factorization.

51151890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 30.

The square root of 51151890 is about 7152.0549494533. The cubic root of 51151890 is about 371.2107645960.

The spelling of 51151890 in words is "fifty-one million, one hundred fifty-one thousand, eight hundred ninety".