661501374 has 32 divisors (see below), whose sum is σ = 1391468544. Its totient is φ = 209358240.

The previous prime is 661501369. The next prime is 661501387. The reversal of 661501374 is 473105166.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23694 + ... + 43409.

It is an arithmetic number, because the mean of its divisors is an integer number (43483392).

Almost surely, 2^661501374 is an apocalyptic number.

661501374 is an abundant number, since it is smaller than the sum of its proper divisors (729967170).

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

661501374 is a wasteful number, since it uses less digits than its factorization.

661501374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67192.

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 661501374 is about 25719.6690103119. The cubic root of 661501374 is about 871.3184633049.

The spelling of 661501374 in words is "six hundred sixty-one million, five hundred one thousand, three hundred seventy-four".