155251890 has 40 divisors (see below), whose sum is σ = 417457260. Its totient is φ = 41400288.

The previous prime is 155251853. The next prime is 155251897. The reversal of 155251890 is 98152551.

It is a happy number.

155251890 is a `hidden beast` number, since 1 + 5 + 52 + 518 + 90 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 139641489 + 15610401 = 11817^2 + 3951^2 .

It is not an unprimeable number, because it can be changed into a prime (155251897) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 95025 + ... + 96644.

Almost surely, 2^155251890 is an apocalyptic number.

155251890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

155251890 is an abundant number, since it is smaller than the sum of its proper divisors (262205370).

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

155251890 is a wasteful number, since it uses less digits than its factorization.

155251890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191688 (or 191679 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 36.

The square root of 155251890 is about 12460.0116372337. The cubic root of 155251890 is about 537.4593616292.

The spelling of 155251890 in words is "one hundred fifty-five million, two hundred fifty-one thousand, eight hundred ninety".